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Arumugam P, Saha K, Nighot P. Intestinal Epithelial Tight Junction Barrier Regulation by Novel Pathways. Inflamm Bowel Dis 2024:izae232. [PMID: 39321109 DOI: 10.1093/ibd/izae232] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/28/2024] [Indexed: 09/27/2024]
Abstract
Intestinal epithelial tight junctions (TJs), a dynamically regulated barrier structure composed of occludin and claudin family of proteins, mediate the interaction between the host and the external environment by allowing selective paracellular permeability between the luminal and serosal compartments of the intestine. TJs are highly dynamic structures and can undergo constant architectural remodeling in response to various external stimuli. This is mediated by an array of intracellular signaling pathways that alters TJ protein expression and localization. Dysfunctional regulation of TJ components compromising the barrier homeostasis is an important pathogenic factor for pathological conditions including inflammatory bowel disease (IBD). Previous studies have elucidated the significance of TJ barrier integrity and key regulatory mechanisms through various in vitro and in vivo models. In recent years, considerable efforts have been made to understand the crosstalk between various signaling pathways that regulate formation and disassembly of TJs. This review provides a comprehensive view on the novel mechanisms that regulate the TJ barrier and permeability. We discuss the latest evidence on how ion transport, cytoskeleton and extracellular matrix proteins, signaling pathways, and cell survival mechanism of autophagy regulate intestinal TJ barrier function. We also provide a perspective on the context-specific outcomes of the TJ barrier modulation. The knowledge on the diverse TJ barrier regulatory mechanisms will provide further insights on the relevance of the TJ barrier defects and potential target molecules/pathways for IBD.
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Affiliation(s)
- Priya Arumugam
- Division of Gastroenterology and Hepatology, Department of Medicine, Pennsylvania State College of Medicine, Hershey, PA, USA
| | - Kushal Saha
- Department of Pathology, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA
| | - Prashant Nighot
- Division of Gastroenterology and Hepatology, Department of Medicine, Pennsylvania State College of Medicine, Hershey, PA, USA
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2
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Zhang SX, Wang JJ, Starr CR, Lee EJ, Park KS, Zhylkibayev A, Medina A, Lin JH, Gorbatyuk M. The endoplasmic reticulum: Homeostasis and crosstalk in retinal health and disease. Prog Retin Eye Res 2024; 98:101231. [PMID: 38092262 PMCID: PMC11056313 DOI: 10.1016/j.preteyeres.2023.101231] [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: 08/21/2023] [Revised: 12/05/2023] [Accepted: 12/06/2023] [Indexed: 12/19/2023]
Abstract
The endoplasmic reticulum (ER) is the largest intracellular organelle carrying out a broad range of important cellular functions including protein biosynthesis, folding, and trafficking, lipid and sterol biosynthesis, carbohydrate metabolism, and calcium storage and gated release. In addition, the ER makes close contact with multiple intracellular organelles such as mitochondria and the plasma membrane to actively regulate the biogenesis, remodeling, and function of these organelles. Therefore, maintaining a homeostatic and functional ER is critical for the survival and function of cells. This vital process is implemented through well-orchestrated signaling pathways of the unfolded protein response (UPR). The UPR is activated when misfolded or unfolded proteins accumulate in the ER, a condition known as ER stress, and functions to restore ER homeostasis thus promoting cell survival. However, prolonged activation or dysregulation of the UPR can lead to cell death and other detrimental events such as inflammation and oxidative stress; these processes are implicated in the pathogenesis of many human diseases including retinal disorders. In this review manuscript, we discuss the unique features of the ER and ER stress signaling in the retina and retinal neurons and describe recent advances in the research to uncover the role of ER stress signaling in neurodegenerative retinal diseases including age-related macular degeneration, inherited retinal degeneration, achromatopsia and cone diseases, and diabetic retinopathy. In some chapters, we highlight the complex interactions between the ER and other intracellular organelles focusing on mitochondria and illustrate how ER stress signaling regulates common cellular stress pathways such as autophagy. We also touch upon the integrated stress response in retinal degeneration and diabetic retinopathy. Finally, we provide an update on the current development of pharmacological agents targeting the UPR response and discuss some unresolved questions and knowledge gaps to be addressed by future research.
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Affiliation(s)
- Sarah X Zhang
- Department of Ophthalmology and Ross Eye Institute, Jacobs School of Medicine and Biomedical Sciences, University at Buffalo, State University of New York, Buffalo, NY, United States; Department of Biochemistry, Jacobs School of Medicine and Biomedical Sciences, University at Buffalo, State University of New York, Buffalo, NY, United States.
| | - Josh J Wang
- Department of Ophthalmology and Ross Eye Institute, Jacobs School of Medicine and Biomedical Sciences, University at Buffalo, State University of New York, Buffalo, NY, United States
| | - Christopher R Starr
- Department of Optometry and Vision Science, University of Alabama at Birmingham, Birmingham, AL, United States
| | - Eun-Jin Lee
- Department of Ophthalmology and Byers Eye Institute, Stanford University, Stanford, CA, United States; VA Palo Alto Healthcare System, Palo Alto, CA, United States; Department of Pathology, Stanford University, Stanford, CA, United States
| | - Karen Sophia Park
- Department of Ophthalmology and Ross Eye Institute, Jacobs School of Medicine and Biomedical Sciences, University at Buffalo, State University of New York, Buffalo, NY, United States
| | - Assylbek Zhylkibayev
- Department of Optometry and Vision Science, University of Alabama at Birmingham, Birmingham, AL, United States
| | - Andy Medina
- Department of Ophthalmology and Ross Eye Institute, Jacobs School of Medicine and Biomedical Sciences, University at Buffalo, State University of New York, Buffalo, NY, United States
| | - Jonathan H Lin
- Department of Ophthalmology and Byers Eye Institute, Stanford University, Stanford, CA, United States; VA Palo Alto Healthcare System, Palo Alto, CA, United States; Department of Pathology, Stanford University, Stanford, CA, United States
| | - Marina Gorbatyuk
- Department of Optometry and Vision Science, University of Alabama at Birmingham, Birmingham, AL, United States
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Wang X, Liu X, Tzekov R, Yu C, Yang J, Feng Y, Wu Y, Xu Y, Li S, Li W. Fenofibrate Ameliorates Retinal Pigment Epithelium Injury Induced by Excessive Fat Through Upregulation of PI3K/AKT Signaling. Drug Des Devel Ther 2023; 17:3439-3452. [PMID: 38024539 PMCID: PMC10676092 DOI: 10.2147/dddt.s420178] [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: 05/06/2023] [Accepted: 11/10/2023] [Indexed: 12/01/2023] Open
Abstract
Purpose This study aimed to determine the effect and its mechanism of fenofibrate on retinal pigment epithelium (RPE) injury induced by excessive fat in vitro and in vivo. Methods ARPE-19 cells were co-incubated with palmitic acid (PA) and fenofibric acid (the active form of fenofibrate after metabolism in vivo) and mice fed with high-fat diet (HFD) were supplemented with fenofibrate. The following methods were used: Western blot and immunofluorescent staining to determine expressions of reactive oxygen species (ROS)-associated factors and proinflammatory cytokines; electroretinogram (ERG) c-wave to evaluate RPE function; TUNEL staining to detect the apoptotic cell in RPE tissue. Additionally, ARPE19 cells were treated with PI3K/AKT inhibitor or agonist to investigate the mechanism of fenofibric acid inhibiting PA-induced RPE damage. Results We found that the application of PA inhibited RPE cell viability in a dose-dependent manner, and increased the levels of NAPDH oxidase 4 (NOX4), 3-nitrotyrosin (3-NT), intracellular adhesion molecule-1(ICAM1), tumor necrosis factor alpha (TNFα) and vascular endothelial growth factor (VEGF) at 400μM. The application of fenofibric acid resulted in the inhibition of NOX4, 3-NT, TNFα, ICAM1 and VEGF expression in ARPE-19 cells treated with PA. Moreover, wortmannin, as a selective inhibitor of PI3K/AKT pathway, abolished the effects of fenofibrate on the oxidative stress and inflammation in ARPE-19 cells. In addition, 740Y-P, a selective agonist of PI3K/AKT pathway, enhanced the protective action of fenofibrate. Meanwhile, in vivo dosing of fenofibrate ameliorated the downregulated amplitudes of ERG c-wave in HFD-fed mice and suppressed the HFD-induced oxidative injury and inflammatory response in RPE tissues. Conclusion Our results suggested that fenofibrate ameliorated RPE cell damage induced by excessive fat in vitro and in vivo, in part, through activation of the PI3K/AKT signaling pathway.
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Affiliation(s)
- Xue Wang
- Aier School of Ophthalmology, Central South University, Changsha, People’s Republic of China
- Suzhou Institute of Biomedical Engineering and Technology, University of Science and Technology of China, Suzhou, People’s Republic of China
- Department of Ophthalmology, Second Affiliated Hospital of Anhui Medical University, Hefei, People’s Republic of China
| | - Xiaomei Liu
- Suzhou Institute of Biomedical Engineering and Technology, University of Science and Technology of China, Suzhou, People’s Republic of China
| | - Radouil Tzekov
- Department of Ophthalmology, University of South Florida, Tampa, FL, USA
| | - Chaofeng Yu
- Aier School of Ophthalmology, Central South University, Changsha, People’s Republic of China
| | - Jiasong Yang
- Aier School of Ophthalmology, Central South University, Changsha, People’s Republic of China
- Shanghai Aier Eye Hospital, Shanghai, People’s Republic of China
| | - Yuliang Feng
- Aier School of Ophthalmology, Central South University, Changsha, People’s Republic of China
| | - Yajun Wu
- Aier School of Ophthalmology, Central South University, Changsha, People’s Republic of China
| | - Yali Xu
- Aier School of Ophthalmology, Central South University, Changsha, People’s Republic of China
| | - Shiying Li
- Department of Ophthalmology, Xiang’an Hospital of Xiamen University, Xiamen University, Xiamen, People’s Republic of China
| | - Wensheng Li
- Aier School of Ophthalmology, Central South University, Changsha, People’s Republic of China
- Shanghai Aier Eye Hospital, Shanghai, People’s Republic of China
- Shanghai Aier Eye Insititute, Shanghai, People’s Republic of China
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Sun WJ, An XD, Zhang YH, Zhao XF, Sun YT, Yang CQ, Kang XM, Jiang LL, Ji HY, Lian FM. The ideal treatment timing for diabetic retinopathy: the molecular pathological mechanisms underlying early-stage diabetic retinopathy are a matter of concern. Front Endocrinol (Lausanne) 2023; 14:1270145. [PMID: 38027131 PMCID: PMC10680169 DOI: 10.3389/fendo.2023.1270145] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/31/2023] [Accepted: 10/23/2023] [Indexed: 12/01/2023] Open
Abstract
Diabetic retinopathy (DR) is a prevalent complication of diabetes, significantly impacting patients' quality of life due to vision loss. No pharmacological therapies are currently approved for DR, excepted the drugs to treat diabetic macular edema such as the anti-VEGF agents or steroids administered by intraocular route. Advancements in research have highlighted the crucial role of early intervention in DR for halting or delaying disease progression. This holds immense significance in enhancing patients' quality of life and alleviating the societal burden associated with medical care costs. The non-proliferative stage represents the early phase of DR. In comparison to the proliferative stage, pathological changes primarily manifest as microangiomas and hemorrhages, while at the cellular level, there is a loss of pericytes, neuronal cell death, and disruption of components and functionality within the retinal neuronal vascular unit encompassing pericytes and neurons. Both neurodegenerative and microvascular abnormalities manifest in the early stages of DR. Therefore, our focus lies on the non-proliferative stage of DR and we have initially summarized the mechanisms involved in its development, including pathways such as polyols, that revolve around the pathological changes occurring during this early stage. We also integrate cutting-edge mechanisms, including leukocyte adhesion, neutrophil extracellular traps, multiple RNA regulation, microorganisms, cell death (ferroptosis and pyroptosis), and other related mechanisms. The current status of drug therapy for early-stage DR is also discussed to provide insights for the development of pharmaceutical interventions targeting the early treatment of DR.
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Affiliation(s)
- Wen-Jie Sun
- Guang’anmen Hospital, China Academy of Chinese Medical Sciences, Beijing, China
- China Academy of Chinese Medical Sciences, Beijing, China
| | - Xue-Dong An
- Guang’anmen Hospital, China Academy of Chinese Medical Sciences, Beijing, China
- China Academy of Chinese Medical Sciences, Beijing, China
| | - Yue-Hong Zhang
- Guang’anmen Hospital, China Academy of Chinese Medical Sciences, Beijing, China
- China Academy of Chinese Medical Sciences, Beijing, China
| | - Xue-Fei Zhao
- Guang’anmen Hospital, China Academy of Chinese Medical Sciences, Beijing, China
- China Academy of Chinese Medical Sciences, Beijing, China
| | - Yu-Ting Sun
- Guang’anmen Hospital, China Academy of Chinese Medical Sciences, Beijing, China
- China Academy of Chinese Medical Sciences, Beijing, China
| | - Cun-Qing Yang
- Guang’anmen Hospital, China Academy of Chinese Medical Sciences, Beijing, China
- China Academy of Chinese Medical Sciences, Beijing, China
| | - Xiao-Min Kang
- Guang’anmen Hospital, China Academy of Chinese Medical Sciences, Beijing, China
- Beijing University of Chinese Medicine, Beijing, China
| | - Lin-Lin Jiang
- Guang’anmen Hospital, China Academy of Chinese Medical Sciences, Beijing, China
- Beijing University of Chinese Medicine, Beijing, China
| | - Hang-Yu Ji
- Guang’anmen Hospital, China Academy of Chinese Medical Sciences, Beijing, China
| | - Feng-Mei Lian
- Guang’anmen Hospital, China Academy of Chinese Medical Sciences, Beijing, China
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5
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Alfonso-Pérez T, Baonza G, Herranz G, Martín-Belmonte F. Deciphering the interplay between autophagy and polarity in epithelial tubulogenesis. Semin Cell Dev Biol 2022; 131:160-172. [PMID: 35641407 DOI: 10.1016/j.semcdb.2022.05.015] [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: 03/04/2022] [Revised: 05/17/2022] [Accepted: 05/18/2022] [Indexed: 12/14/2022]
Abstract
The Metazoan complexity arises from a primary building block, the epithelium, which comprises a layer of polarized cells that divide the organism into compartments. Most of these body compartments are organs formed by epithelial tubes that enclose an internal hollow space or lumen. Over the last decades, multiple studies have unmasked the paramount events required to form this lumen de novo. In epithelial cells, these events mainly involve recognizing external clues, establishing and maintaining apicobasal polarity, endo-lysosomal trafficking, and expanding the created lumen. Although canonical autophagy has been classically considered a catabolic process needed for cell survival, multiple studies have also emphasized its crucial role in epithelial polarity, morphogenesis and cellular homeostasis. Furthermore, non-canonical autophagy pathways have been recently discovered as atypical secretory routes. Both canonical and non-canonical pathways play essential roles in epithelial polarity and lumen formation. This review addresses how the molecular machinery for epithelial polarity and autophagy interplay in different processes and how autophagy functions influence lumenogenesis, emphasizing its role in the lumen formation key events.
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Affiliation(s)
- Tatiana Alfonso-Pérez
- Program of Tissue and Organ Homeostasis, Centro de Biología Molecular "Severo, Ochoa", CSIC-UAM, Madrid 28049, Spain; Ramon & Cajal Health Research Institute (IRYCIS), Hospital Universitario Ramón y Cajal, Madrid 28034, Spain
| | - Gabriel Baonza
- Program of Tissue and Organ Homeostasis, Centro de Biología Molecular "Severo, Ochoa", CSIC-UAM, Madrid 28049, Spain
| | - Gonzalo Herranz
- Program of Tissue and Organ Homeostasis, Centro de Biología Molecular "Severo, Ochoa", CSIC-UAM, Madrid 28049, Spain; Ramon & Cajal Health Research Institute (IRYCIS), Hospital Universitario Ramón y Cajal, Madrid 28034, Spain
| | - Fernando Martín-Belmonte
- Program of Tissue and Organ Homeostasis, Centro de Biología Molecular "Severo, Ochoa", CSIC-UAM, Madrid 28049, Spain; Ramon & Cajal Health Research Institute (IRYCIS), Hospital Universitario Ramón y Cajal, Madrid 28034, Spain.
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6
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Han X, Lv Q, Liu H, Dai R, Liu J, Shen Q, Sun L, Rao J, Chen J, Zhai Y, Xu H. PPARα agonist exerts protective effects in podocyte injury via inhibition of the ANGPTL3 pathway. Exp Cell Res 2021; 407:112753. [PMID: 34499887 DOI: 10.1016/j.yexcr.2021.112753] [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: 02/17/2021] [Revised: 07/12/2021] [Accepted: 07/26/2021] [Indexed: 11/29/2022]
Abstract
Peroxisome proliferator-activated receptor α (PPARα) activation has been reported to exert protective effects on podocytes, whereas angiopoietin-like 3 (ANGPTL3) has been shown to exert significant pathogenic effects on these cells. This study aimed to investigate the link between the protective effects of PPARα activation and the pathogenic effects of ANGPTL3 in podocytes. Both PPARα and ANGPTL3 were expressed in cultured podocytes. PPARα mRNA and protein levels decreased whereas ANGPTL3 mRNA and protein levels increased in a time-dependent manner in podocytes treated with puromycin aminonucleoside (PAN). Gemfibrozil, a pharmacological agonist of PPARα, increased PPARα levels and activity in podocytes. The drug also decreased ANGPTL3 levels by potentially weakening ANGPTL3 promoter activity in both normal and PAN-treated podocytes. Furthermore, gemfibrozil significantly decreased PAN-induced apoptosis and F-actin rearrangement. Primary podocytes from Angptl3-knockout mice were cultured. There was no significant difference between Angptl3-/- podocytes treated with or without gemfibrozil in the lamellipodia numbers after PAN treatment. The results suggested that the protective effects of gemfibrozil on podocytes were not exerted following knockout of the Angptl3 gene. This study identified a novel mechanism of the PPARα agonist gemfibrozil that exerts its protective effects by inhibiting PAN-induced apoptosis and cytoskeleton rearrangements through inhibition of ANGPTL3 expression.
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Affiliation(s)
- Xinli Han
- Department of Nephrology, Children's Hospital of Fudan University, Shanghai, China; Kidney Development and Pediatric Kidney Disease Research Center, Shanghai, China
| | - Qianying Lv
- Department of Nephrology, Children's Hospital of Fudan University, Shanghai, China; Kidney Development and Pediatric Kidney Disease Research Center, Shanghai, China
| | - Haimei Liu
- Department of Rheumatology, Children's Hospital of Fudan University, Shanghai, China
| | - Rufeng Dai
- Department of Nephrology, Children's Hospital of Fudan University, Shanghai, China; Kidney Development and Pediatric Kidney Disease Research Center, Shanghai, China
| | - Jiaojiao Liu
- Department of Nephrology, Children's Hospital of Fudan University, Shanghai, China; Kidney Development and Pediatric Kidney Disease Research Center, Shanghai, China
| | - Qian Shen
- Department of Nephrology, Children's Hospital of Fudan University, Shanghai, China; Kidney Development and Pediatric Kidney Disease Research Center, Shanghai, China
| | - Li Sun
- Department of Rheumatology, Children's Hospital of Fudan University, Shanghai, China
| | - Jia Rao
- Department of Nephrology, Children's Hospital of Fudan University, Shanghai, China; Kidney Development and Pediatric Kidney Disease Research Center, Shanghai, China
| | - Jing Chen
- Department of Nephrology, Children's Hospital of Fudan University, Shanghai, China; Kidney Development and Pediatric Kidney Disease Research Center, Shanghai, China
| | - Yihui Zhai
- Department of Nephrology, Children's Hospital of Fudan University, Shanghai, China; Kidney Development and Pediatric Kidney Disease Research Center, Shanghai, China.
| | - Hong Xu
- Department of Nephrology, Children's Hospital of Fudan University, Shanghai, China; Kidney Development and Pediatric Kidney Disease Research Center, Shanghai, China.
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7
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Simó R, Simó-Servat O, Bogdanov P, Hernández C. Neurovascular Unit: A New Target for Treating Early Stages of Diabetic Retinopathy. Pharmaceutics 2021; 13:pharmaceutics13081320. [PMID: 34452281 PMCID: PMC8399715 DOI: 10.3390/pharmaceutics13081320] [Citation(s) in RCA: 24] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2021] [Revised: 08/18/2021] [Accepted: 08/19/2021] [Indexed: 01/02/2023] Open
Abstract
The concept of diabetic retinopathy as a microvascular disease has evolved and is now considered a more complex diabetic complication in which neurovascular unit impairment plays an essential role and, therefore, can be considered as a main therapeutic target in the early stages of the disease. However, neurodegeneration is not always the apparent primary event in the natural story of diabetic retinopathy, and a phenotyping characterization is recommendable to identify those patients in whom neuroprotective treatment might be of benefit. In recent years, a myriad of treatments based on neuroprotection have been tested in experimental models, but more interestingly, there are drugs with a dual activity (neuroprotective and vasculotropic). In this review, the recent evidence concerning the therapeutic approaches targeting neurovascular unit impairment will be presented, along with a critical review of the scientific gaps and problems which remain to be overcome before our knowledge can be transferred to clinical practice.
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Affiliation(s)
- Rafael Simó
- Diabetes and Metabolism Research Unit, Vall d’Hebron Research Institute (VHIR), 08035 Barcelona, Spain; (O.S.-S.); (P.B.); (C.H.)
- Centro de Investigación Biomédica en Red de Diabetes y Enfermedades Metabólicas Asociadas (CIBERDEM), Instituto de Salud Carlos III (ICSIII), 28029 Madrid, Spain
- Correspondence:
| | - Olga Simó-Servat
- Diabetes and Metabolism Research Unit, Vall d’Hebron Research Institute (VHIR), 08035 Barcelona, Spain; (O.S.-S.); (P.B.); (C.H.)
- Centro de Investigación Biomédica en Red de Diabetes y Enfermedades Metabólicas Asociadas (CIBERDEM), Instituto de Salud Carlos III (ICSIII), 28029 Madrid, Spain
| | - Patricia Bogdanov
- Diabetes and Metabolism Research Unit, Vall d’Hebron Research Institute (VHIR), 08035 Barcelona, Spain; (O.S.-S.); (P.B.); (C.H.)
- Centro de Investigación Biomédica en Red de Diabetes y Enfermedades Metabólicas Asociadas (CIBERDEM), Instituto de Salud Carlos III (ICSIII), 28029 Madrid, Spain
| | - Cristina Hernández
- Diabetes and Metabolism Research Unit, Vall d’Hebron Research Institute (VHIR), 08035 Barcelona, Spain; (O.S.-S.); (P.B.); (C.H.)
- Centro de Investigación Biomédica en Red de Diabetes y Enfermedades Metabólicas Asociadas (CIBERDEM), Instituto de Salud Carlos III (ICSIII), 28029 Madrid, Spain
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8
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Adornetto A, Gesualdo C, Laganà ML, Trotta MC, Rossi S, Russo R. Autophagy: A Novel Pharmacological Target in Diabetic Retinopathy. Front Pharmacol 2021; 12:695267. [PMID: 34234681 PMCID: PMC8256993 DOI: 10.3389/fphar.2021.695267] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2021] [Accepted: 06/09/2021] [Indexed: 01/18/2023] Open
Abstract
Autophagy is the major catabolic pathway involved in removing and recycling damaged macromolecules and organelles and several evidences suggest that dysfunctions of this pathway contribute to the onset and progression of central and peripheral neurodegenerative diseases. Diabetic retinopathy (DR) is a serious complication of diabetes mellitus representing the main preventable cause of acquired blindness worldwide. DR has traditionally been considered as a microvascular disease, however this concept has evolved and neurodegeneration and neuroinflammation have emerged as important determinants in the pathogenesis and evolution of the retinal pathology. Here we review the role of autophagy in experimental models of DR and explore the potential of this pathway as a target for alternative therapeutic approaches.
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Affiliation(s)
- Annagrazia Adornetto
- Preclinical and Translational Pharmacology, Department of Pharmacy, Health and Nutritional Sciences, University of Calabria, Rende, Italy
| | - Carlo Gesualdo
- Multidisciplinary Department of Medical, Surgical and Dental Sciences, University of Campania “Luigi Vanvitelli”, Naples, Italy
| | - Maria Luisa Laganà
- Preclinical and Translational Pharmacology, Department of Pharmacy, Health and Nutritional Sciences, University of Calabria, Rende, Italy
| | - Maria Consiglia Trotta
- Department of Experimental Medicine, University of Campania “Luigi Vanvitelli”, Naples, Italy
| | - Settimio Rossi
- Multidisciplinary Department of Medical, Surgical and Dental Sciences, University of Campania “Luigi Vanvitelli”, Naples, Italy
| | - Rossella Russo
- Preclinical and Translational Pharmacology, Department of Pharmacy, Health and Nutritional Sciences, University of Calabria, Rende, Italy
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9
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Feng L, Liang L, Zhang S, Yang J, Yue Y, Zhang X. HMGB1 downregulation in retinal pigment epithelial cells protects against diabetic retinopathy through the autophagy-lysosome pathway. Autophagy 2021; 18:320-339. [PMID: 34024230 PMCID: PMC8942416 DOI: 10.1080/15548627.2021.1926655] [Citation(s) in RCA: 39] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
Diabetic retinopathy (DR) is a serious complication of diabetes mellitus and currently one of the major causes of blindness. Several previous studies have demonstrated that autophagy, which is regulated by HMGB1 (high mobility group box 1), is involved in DR development. However, the role of autophagy in DR is quite complicated in that it promotes pericyte survival in early DR, whereas excessive autophagy causes excess stress and leads to necrosis. Therefore, this study aimed to investigate the relationship between HMGB1, the macroautophagy/autophagy-lysosome pathway, and DR, as well as their underlying molecular mechanisms. In brief, the relationship between high glucose (HG) and the autophagy-lysosome pathway was examined in retinal pigment epithelial (RPE) cells. The relationship was studied by detecting classical autophagic features, and siRNAs targeting HMGB1 and pharmacological regulators were used to explore the role of the autophagy-lysosome pathway in DR development. The results demonstrated that HG inhibited autophagy and diminished the degradative capacity of autophagy due to lysosome membrane permeabilization (LMP). In addition, HMGB1 was found to be involved in LMP via the CTSB (cathepsin B)-dependent pathway, but not the CTSL (cathepsin L)-dependent pathway. Knockdown of HMGB1 expression rescued LMP, restored the degradative capacity of autophagy, decreased the expression of inflammatory factors and VEGF (vascular endothelial growth factor), and protected against apoptosis in RPE cells in the early stages of DR.
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Affiliation(s)
- Lujia Feng
- Chongqing Key Lab of Ophthalmology, The First Affiliated Hospital of Chongqing Medical University, Chongqing Eye Institute, Chongqing Branch of National Clinical Research Center for Ocular Diseases, Chongqing, P. R. China
| | - Liang Liang
- Chongqing Key Lab of Ophthalmology, The First Affiliated Hospital of Chongqing Medical University, Chongqing Eye Institute, Chongqing Branch of National Clinical Research Center for Ocular Diseases, Chongqing, P. R. China
| | - Shaochong Zhang
- Shenzhen Key Laboratory of Ophthalmology, Ophthalmology, Shenzhen Eye Hospital, Shenzhen, Guangdong, China
| | - Jinglu Yang
- Chongqing Key Lab of Ophthalmology, The First Affiliated Hospital of Chongqing Medical University, Chongqing Eye Institute, Chongqing Branch of National Clinical Research Center for Ocular Diseases, Chongqing, P. R. China
| | - Yanan Yue
- Chongqing Key Lab of Ophthalmology, The First Affiliated Hospital of Chongqing Medical University, Chongqing Eye Institute, Chongqing Branch of National Clinical Research Center for Ocular Diseases, Chongqing, P. R. China
| | - Xuedong Zhang
- Chongqing Key Lab of Ophthalmology, The First Affiliated Hospital of Chongqing Medical University, Chongqing Eye Institute, Chongqing Branch of National Clinical Research Center for Ocular Diseases, Chongqing, P. R. China
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10
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Zhang Q, Presswalla F, Ali RR, Zacks DN, Thompson DA, Miller JML. Pharmacologic activation of autophagy without direct mTOR inhibition as a therapeutic strategy for treating dry macular degeneration. Aging (Albany NY) 2021; 13:10866-10890. [PMID: 33872219 PMCID: PMC8109132 DOI: 10.18632/aging.202974] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2020] [Accepted: 03/13/2021] [Indexed: 12/15/2022]
Abstract
Dry age-related macular degeneration (AMD) is marked by the accumulation of extracellular and intracellular lipid-rich deposits within and around the retinal pigment epithelium (RPE). Inducing autophagy, a conserved, intracellular degradative pathway, is a potential treatment strategy to prevent disease by clearing these deposits. However, mTOR inhibition, the major mechanism for inducing autophagy, disrupts core RPE functions. Here, we screened autophagy inducers that do not directly inhibit mTOR for their potential as an AMD therapeutic in primary human RPE culture. Only two out of more than thirty autophagy inducers tested reliably increased autophagy flux in RPE, emphasizing that autophagy induction mechanistically differs across distinct tissues. In contrast to mTOR inhibitors, these compounds preserved RPE health, and one inducer, the FDA-approved compound flubendazole (FLBZ), reduced the secretion of apolipoprotein that contributes to extracellular deposits termed drusen. Simultaneously, FLBZ increased production of the lipid-degradation product β-hydroxybutyrate, which is used by photoreceptor cells as an energy source. FLBZ also reduced the accumulation of intracellular deposits, termed lipofuscin, and alleviated lipofuscin-induced cellular senescence and tight-junction disruption. FLBZ triggered compaction of lipofuscin-like granules into a potentially less toxic form. Thus, induction of RPE autophagy without direct mTOR inhibition is a promising therapeutic approach for dry AMD.
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Affiliation(s)
- Qitao Zhang
- Kellogg Eye Center, University of Michigan, Ann Arbor, MI 48105, USA
| | - Feriel Presswalla
- Kellogg Eye Center, University of Michigan, Ann Arbor, MI 48105, USA
| | - Robin R. Ali
- Kellogg Eye Center, University of Michigan, Ann Arbor, MI 48105, USA
- KCL Centre for Cell and Gene Therapy, London, England WC2R 2LS, United Kingdom
| | - David N. Zacks
- Kellogg Eye Center, University of Michigan, Ann Arbor, MI 48105, USA
| | - Debra A. Thompson
- Kellogg Eye Center, University of Michigan, Ann Arbor, MI 48105, USA
- Department of Biological Chemistry, University of Michigan, Ann Arbor, MI 48105, USA
| | - Jason ML. Miller
- Kellogg Eye Center, University of Michigan, Ann Arbor, MI 48105, USA
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11
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Gong Q, Wang H, Yu P, Qian T, Xu X. Protective or Harmful: The Dual Roles of Autophagy in Diabetic Retinopathy. Front Med (Lausanne) 2021; 8:644121. [PMID: 33842506 PMCID: PMC8026897 DOI: 10.3389/fmed.2021.644121] [Citation(s) in RCA: 28] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2020] [Accepted: 02/26/2021] [Indexed: 12/19/2022] Open
Abstract
Autophagy is a self-degradative pathway involving intracellular substance degradation and recycling. Recently, this process has attracted a great deal of attention for its fundamental effect on physiological processes in cells, tissues, and the maintenance of organismal homeostasis. Dysregulation of autophagy occurs in some diseases, including immune disease, cancer, and neurodegenerative conditions. Diabetic retinopathy (DR), as a serious microvascular complication of diabetes, is the main cause of visual loss in working-age adults worldwide. The pathogenic mechanisms of DR are thought to be associated with accumulation of oxidative stress, retinal cell apoptosis, inflammatory response, endoplasmic reticulum (ER) stress, and nutrient starvation. These factors are closely related to the regulation of autophagy under pathological conditions. Increasing evidence has demonstrated the potential role of autophagy in the progression of DR through different pathways. However, to date this role is not understood, and whether the altered level of autophagy flux protects DR, or instead aggravates the progression, needs to be explored. In this review, we explore the alterations and functions of autophagy in different retinal cells and tissues under DR conditions, and explain the mechanisms involved in DR progression. We aim to provide a basis on which DR associated stress-modulated autophagy may be understood, and to suggest novel targets for future therapeutic intervention in DR.
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Affiliation(s)
- Qiaoyun Gong
- Shanghai Key Laboratory of Ocular Fundus Diseases, Department of Ophthalmology, National Clinical Research Center for Eye Diseases, Shanghai Engineering Center for Visual Science and Photomedicine, Shanghai Engineering Center for Precise Diagnosis and Treatment of Eye Diseases, Shanghai General Hospital, Shanghai, China
| | - Haiyan Wang
- Shanghai Key Laboratory of Ocular Fundus Diseases, Department of Ophthalmology, National Clinical Research Center for Eye Diseases, Shanghai Engineering Center for Visual Science and Photomedicine, Shanghai Engineering Center for Precise Diagnosis and Treatment of Eye Diseases, Shanghai General Hospital, Shanghai, China
| | - Ping Yu
- Department of Pharmacy, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Tianwei Qian
- Shanghai Key Laboratory of Ocular Fundus Diseases, Department of Ophthalmology, National Clinical Research Center for Eye Diseases, Shanghai Engineering Center for Visual Science and Photomedicine, Shanghai Engineering Center for Precise Diagnosis and Treatment of Eye Diseases, Shanghai General Hospital, Shanghai, China
| | - Xun Xu
- Shanghai Key Laboratory of Ocular Fundus Diseases, Department of Ophthalmology, National Clinical Research Center for Eye Diseases, Shanghai Engineering Center for Visual Science and Photomedicine, Shanghai Engineering Center for Precise Diagnosis and Treatment of Eye Diseases, Shanghai General Hospital, Shanghai, China
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12
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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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13
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Kim MH, Kwon SY, Woo SY, Seo WD, Kim DY. Antioxidative Effects of Chrysoeriol via Activation of the Nrf2 Signaling Pathway and Modulation of Mitochondrial Function. Molecules 2021; 26:molecules26020313. [PMID: 33435366 PMCID: PMC7826659 DOI: 10.3390/molecules26020313] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2020] [Revised: 12/30/2020] [Accepted: 01/06/2021] [Indexed: 02/07/2023] Open
Abstract
Retinal pigment epithelium (RPE) cell dysfunction caused by excessive oxidative damage is partly involved in age-related macular degeneration, which is among the leading causes of visual impairment in elderly people. Here, we investigated the protective role of chrysoeriol against hydrogen peroxide (H2O2)-induced oxidative stress in RPE cells. The cellular viability, reactive oxygen species (ROS) generation, and mitochondrial function of retinal ARPE-19 cells were monitored under oxidative stress or pre-treatment with chrysoeriol. The expression levels of mitochondrial-related genes and associated transcription factors were assessed using reverse transcription-quantitative polymerase chain reaction (RT-qPCR). Moreover, the protein expression of antioxidant signal molecules was characterized by Western blot analysis. Chrysoeriol significantly increased cell viability, reduced ROS generation, and increased the occurrence of antioxidant molecules in H2O2-treated ARPE-19 cells. Additionally, mitochondrial dysfunction caused by H2O2-induced oxidative stress was also considerably diminished by chrysoeriol treatment, which reduced the mitochondrial membrane potential (MMP) and upregulated mitochondrial-associated genes and proteins. Chrysoeriol also markedly enhanced key transcription factors (Nrf2) and antioxidant-associated genes (particularly HO-1 and NQO-1). Therefore, our study confirms the protective effect of chrysoeriol against H2O2-induced oxidative stress in RPE cells, thus confirming that it may prevent mitochondrial dysfunction by upregulating antioxidant-related molecules.
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Affiliation(s)
- Myung Hee Kim
- Inha Research Institute for Aerospace Medicine, Inha University, Incheon 22212, Korea;
| | - So Yeon Kwon
- Department of Mechanical Engineering, College of Engineering, Inha University, Incheon 22212, Korea;
| | - So-Yeun Woo
- Rural Development Administration, National Institute of Crop Science, Wanju-gun, Jeollabuk-do 55365, Korea; (S.-Y.W.); (W.D.S.)
| | - Woo Duck Seo
- Rural Development Administration, National Institute of Crop Science, Wanju-gun, Jeollabuk-do 55365, Korea; (S.-Y.W.); (W.D.S.)
| | - Dae Yu Kim
- Inha Research Institute for Aerospace Medicine, Inha University, Incheon 22212, Korea;
- Department of Electrical Engineering and Center for Sensor Systems, College of Engineering, Inha University, Incheon 22212, Korea
- Correspondence: ; Tel.: +82-32-860-7394
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14
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Effect of Topical Administration of Somatostatin on Retinal Inflammation and Neurodegeneration in an Experimental Model of Diabetes. J Clin Med 2020; 9:jcm9082579. [PMID: 32784955 PMCID: PMC7463891 DOI: 10.3390/jcm9082579] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2020] [Revised: 07/25/2020] [Accepted: 08/04/2020] [Indexed: 12/11/2022] Open
Abstract
Somatostatin (SST) is a neuroprotective peptide but little is known regarding the potential role of its anti-inflammatory effects on retinal neuroprotection. In a previous study, we provided the first evidence that topical (eye drops) administration of SST prevents retinal neurodegeneration in streptozotocin (STZ)-induced diabetic rats. However, STZ by itself could cause neurotoxicity, thus acting as a confounding factor. The aims of the present study were: (1) to test the effect of topical administration of SST in the db/db mouse model, a spontaneous model of type 2 diabetes, thus avoiding the confounding effect of STZ on neurodegeneration; (2) to further explore the anti-inflammatory mechanisms of SST in glial cells. This task was performed by using mouse retinal explants and cell cultures. In summary, we confirm that SST topically administered was able to prevent retinal neurodysfunction and neurodegeneration in db/db mice. Furthermore, we found that SST prevented the activation of the classical M1 response of Bv.2 microglial cells upon Lipopolysaccharide (LPS) stimulation as a potent pro-inflammatory trigger. The anti-inflammatory effect of SST in Bv.2 cells was also observed in response to hypoxia. In conclusion, we provide evidence that the neuroprotective effect of SST in diabetic retinas can be largely attributed to anti-inflammatory mechanisms.
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15
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Hsu YJ, Lin CW, Cho SL, Yang WS, Yang CM, Yang CH. Protective Effect of Fenofibrate on Oxidative Stress-Induced Apoptosis in Retinal-Choroidal Vascular Endothelial Cells: Implication for Diabetic Retinopathy Treatment. Antioxidants (Basel) 2020; 9:antiox9080712. [PMID: 32764528 PMCID: PMC7464418 DOI: 10.3390/antiox9080712] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2020] [Revised: 07/28/2020] [Accepted: 08/04/2020] [Indexed: 12/24/2022] Open
Abstract
Diabetic retinopathy (DR) is an important microvascular complication of diabetes and one of the leading causes of blindness in developed countries. Two large clinical studies showed that fenofibrate, a peroxisome proliferator-activated receptor type α (PPAR-α) agonist, reduces DR progression. We evaluated the protective effects of fenofibrate on retinal/choroidal vascular endothelial cells under oxidative stress and investigated the underlying mechanisms using RF/6A cells as the model system and paraquat (PQ) to induce oxidative stress. Pretreatment with fenofibrate suppressed reactive oxygen species (ROS) production, decreased cellular apoptosis, diminished the changes in the mitochondrial membrane potential, increased the mRNA levels of peroxiredoxin (Prx), thioredoxins (Trxs), B-cell lymphoma 2 (Bcl-2), and Bcl-xl, and reduced the level of B-cell lymphoma 2-associated X protein (Bax) in PQ-stimulated RF/6A cells. Western blot analysis revealed that fenofibrate repressed apoptosis through cytosolic and mitochondrial apoptosis signal-regulated kinase-1 (Ask)-Trx-related signaling pathways, including c-Jun amino-terminal kinase (JNK) phosphorylation, cytochrome c release, caspase 3 activation, and poly (ADP-ribose) polymerase-1 (PARP-1) cleavage. These protective effects of fenofibrate on RF/6A cells may be attributable to its anti-oxidative ability. Our research suggests that fenofibrate could serve as an effective adjunct therapy for ocular oxidative stress-related disorders, such as DR.
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Affiliation(s)
- Ying-Jung Hsu
- Graduate Institute of Clinical Medicine, College of Medicine, National Taiwan University, No. 1, Jen Ai Road Section 1, Taipei 100, Taiwan; (Y.-J.H.); (C.-W.L.); (W.-S.Y.)
| | - Chao-Wen Lin
- Graduate Institute of Clinical Medicine, College of Medicine, National Taiwan University, No. 1, Jen Ai Road Section 1, Taipei 100, Taiwan; (Y.-J.H.); (C.-W.L.); (W.-S.Y.)
- Department of Ophthalmology, National Taiwan University Hospital, No. 7, Zhongshan South Road, Taipei 100, Taiwan;
| | - Sheng-Li Cho
- Department of Internal Medicine, National Taiwan University Hospital, No. 7, Zhongshan South Road, Taipei 100, Taiwan;
| | - Wei-Shiung Yang
- Graduate Institute of Clinical Medicine, College of Medicine, National Taiwan University, No. 1, Jen Ai Road Section 1, Taipei 100, Taiwan; (Y.-J.H.); (C.-W.L.); (W.-S.Y.)
- Department of Internal Medicine, National Taiwan University Hospital, No. 7, Zhongshan South Road, Taipei 100, Taiwan;
| | - Chung-May Yang
- Department of Ophthalmology, National Taiwan University Hospital, No. 7, Zhongshan South Road, Taipei 100, Taiwan;
| | - Chang-Hao Yang
- Department of Ophthalmology, National Taiwan University Hospital, No. 7, Zhongshan South Road, Taipei 100, Taiwan;
- Correspondence: ; Tel.: +886-2-23123456 (ext. 63193)
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16
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Zhang C, Xie H, Yang Q, Yang Y, Li W, Tian H, Lu L, Wang F, Xu JY, Gao F, Wang J, Jin C, Xu G, Xu GT, Zhang J. Erythropoietin protects outer blood-retinal barrier in experimental diabetic retinopathy by up-regulating ZO-1 and occludin. Clin Exp Ophthalmol 2019; 47:1182-1197. [PMID: 31483932 DOI: 10.1111/ceo.13619] [Citation(s) in RCA: 33] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2018] [Revised: 08/25/2019] [Accepted: 08/26/2019] [Indexed: 01/29/2023]
Abstract
PURPOSE To explore the mechanisms of erythropoietin (EPO) in maintaining outer blood-retinal barrier (BRB) in diabetic rats. METHODS Sprague-Dawley rats were rendered diabetic with intraperitoneal injection of streptozotocin, and then followed by intravitreal injection of EPO. Two and four weeks later, the permeability of outer BRB was examined with FITC-dextran leakage assay, following a method to demarcate the inner and outer retina based on retinal blood supply. The glyoxal-treated ARPE-19 cells, incubated with EPO, soluble EPO receptor (sEPOR), Gö6976, or digoxin, were studied for cell viability and barrier function. The expressions of ZO-1, occludin, VEGFR2, HIF-1α, MAPKs, and AKT were examined with Western blot and immunofluorescence. RESULTS The major Leakage of FITC-dextran was detected in the outer nuclear layer in both 2- and 4-week diabetic rats. The leakage was largely ameliorated in EPO-treated diabetic rats. The protein expressions of ZO-1 and occludin in the RPE-Bruch's membrane choriocapillaris complex were significantly decreased, whereas HIF-1α and JNK pathways were activated, in 4-week diabetic rats. These changes were prevented by EPO treatment. The in vitro study with ARPE-19 cells confirmed these changes, and the protective effect of EPO was abolished by sEPOR. Gö6976 and digoxin rescued the tight junction and barrier function in glyoxal-treated ARPE-19 cells. CONCLUSIONS In early diabetic rats, the outer BRB might be more severely damaged and its breakdown is the major factor for retinal oedema. EPO maintains the outer BRB integrity through down-regulation of HIF-1α and JNK signallings, and thus up-regulating ZO-1 and occludin expressions in RPE cells.
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Affiliation(s)
- Chaoyang Zhang
- Department of Ophthalmology of Shanghai Tenth People's Hospital, Tongji Eye Institute, Tongji University School of Medicine, Shanghai, China.,Department of Regenerative Medicine, Tongji University School of Medicine, Shanghai, China.,Department of Pharmacology, Tongji University School of Medicine, Shanghai, China
| | - Hai Xie
- Department of Ophthalmology of Shanghai Tenth People's Hospital, Tongji Eye Institute, Tongji University School of Medicine, Shanghai, China.,Department of Regenerative Medicine, Tongji University School of Medicine, Shanghai, China.,Department of Pharmacology, Tongji University School of Medicine, Shanghai, China
| | - Qian Yang
- Department of Ophthalmology of Shanghai Tenth People's Hospital, Tongji Eye Institute, Tongji University School of Medicine, Shanghai, China.,Department of Regenerative Medicine, Tongji University School of Medicine, Shanghai, China.,Department of Pharmacology, Tongji University School of Medicine, Shanghai, China
| | - Yiting Yang
- Department of Ophthalmology of Shanghai Tenth People's Hospital, Tongji Eye Institute, Tongji University School of Medicine, Shanghai, China.,Department of Regenerative Medicine, Tongji University School of Medicine, Shanghai, China.,Department of Pharmacology, Tongji University School of Medicine, Shanghai, China
| | - Weiye Li
- Department of Ophthalmology of Shanghai Tenth People's Hospital, Tongji Eye Institute, Tongji University School of Medicine, Shanghai, China.,Department of Regenerative Medicine, Tongji University School of Medicine, Shanghai, China.,Department of Pharmacology, Tongji University School of Medicine, Shanghai, China.,Department of Ophthalmology, Drexel University College of Medicine, Philadelphia, Pennsylvania
| | - Haibin Tian
- Department of Ophthalmology of Shanghai Tenth People's Hospital, Tongji Eye Institute, Tongji University School of Medicine, Shanghai, China.,Department of Regenerative Medicine, Tongji University School of Medicine, Shanghai, China.,Department of Pharmacology, Tongji University School of Medicine, Shanghai, China
| | - Lixia Lu
- Department of Ophthalmology of Shanghai Tenth People's Hospital, Tongji Eye Institute, Tongji University School of Medicine, Shanghai, China.,Department of Regenerative Medicine, Tongji University School of Medicine, Shanghai, China.,Department of Pharmacology, Tongji University School of Medicine, Shanghai, China
| | - Fang Wang
- Department of Ophthalmology of Shanghai Tenth People's Hospital, Tongji Eye Institute, Tongji University School of Medicine, Shanghai, China.,Department of Regenerative Medicine, Tongji University School of Medicine, Shanghai, China.,Department of Pharmacology, Tongji University School of Medicine, Shanghai, China
| | - Jing-Ying Xu
- Department of Ophthalmology of Shanghai Tenth People's Hospital, Tongji Eye Institute, Tongji University School of Medicine, Shanghai, China.,Department of Regenerative Medicine, Tongji University School of Medicine, Shanghai, China.,Department of Pharmacology, Tongji University School of Medicine, Shanghai, China
| | - Furong Gao
- Department of Ophthalmology of Shanghai Tenth People's Hospital, Tongji Eye Institute, Tongji University School of Medicine, Shanghai, China.,Department of Regenerative Medicine, Tongji University School of Medicine, Shanghai, China.,Department of Pharmacology, Tongji University School of Medicine, Shanghai, China
| | - Juan Wang
- Department of Ophthalmology of Shanghai Tenth People's Hospital, Tongji Eye Institute, Tongji University School of Medicine, Shanghai, China.,Department of Regenerative Medicine, Tongji University School of Medicine, Shanghai, China.,Department of Pharmacology, Tongji University School of Medicine, Shanghai, China
| | - Caixia Jin
- Department of Ophthalmology of Shanghai Tenth People's Hospital, Tongji Eye Institute, Tongji University School of Medicine, Shanghai, China.,Department of Regenerative Medicine, Tongji University School of Medicine, Shanghai, China.,Department of Pharmacology, Tongji University School of Medicine, Shanghai, China
| | - Guoxu Xu
- Department of Ophthalmology, The Second Affiliated Hospital of Soochow University, Suzhou, China
| | - Guo-Tong Xu
- Department of Ophthalmology of Shanghai Tenth People's Hospital, Tongji Eye Institute, Tongji University School of Medicine, Shanghai, China.,Department of Regenerative Medicine, Tongji University School of Medicine, Shanghai, China.,Department of Pharmacology, Tongji University School of Medicine, Shanghai, China
| | - Jingfa Zhang
- Department of Ophthalmology of Shanghai Tenth People's Hospital, Tongji Eye Institute, Tongji University School of Medicine, Shanghai, China.,Department of Regenerative Medicine, Tongji University School of Medicine, Shanghai, China.,Department of Pharmacology, Tongji University School of Medicine, Shanghai, China.,Department of Ophthalmology, Shanghai General Hospital (Shanghai First People's Hospital), Shanghai Jiao Tong University, School of Medicine, Shanghai, China.,Shanghai Key Laboratory of Ocular Fundus Diseases, Shanghai, China.,National Center for Clinical Research of Ophthalmology, Shanghai, China
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17
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Maugeri G, D'Amico AG, Bucolo C, D'Agata V. Protective effect of PACAP-38 on retinal pigmented epithelium in an in vitro and in vivo model of diabetic retinopathy through EGFR-dependent mechanism. Peptides 2019; 119:170108. [PMID: 31247223 DOI: 10.1016/j.peptides.2019.170108] [Citation(s) in RCA: 31] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/25/2019] [Revised: 06/20/2019] [Accepted: 06/24/2019] [Indexed: 11/22/2022]
Abstract
Diabetic retinopathy (DR) is one of the most common microvascular complications of diabetes. In the last years, several in vivo studies have demonstrated the protective role of pituitary adenylate cyclase-activating peptide (PACAP-38) to counteract several alterations occurring during DR. Recently, different studies have demonstrated that some PACAP-38 effects are mediated by EGFR trans-activation, although no data exist regarding the link between this peptide and EGFR in DR. The aim of the present study has been to investigate whether retinal effect of PACAP-38 against high glucose damage is mediated by EGFR phosphorylation. Diabetes was induced by a single injection of streptozotocin (STZ) in rats. After 1 week, a group of animals was treated with a single intravitreal injection of 100 μM PACAP-38 or saline solution. Immunohistochemistry and western blot analysis have demonstrated that intravitreal injection of PACAP-38 induced p-EGFR over-expression in retina of diabetic rats. Several pathogenic mechanisms may contribute to diabetic retinopathy including BRB alteration. To better clarify the relationship between PACAP-38 and EGFR, we have also carried out a study on ARPE-19 cells, representing a model in vitro of outer BRB. Our results have shown that PACAP-38 treatment improved cell viability in ARPE-19 cells exposed to hyperglycemic/hypoxic insult mimicking tissue microenvironment occurring in DR. Binding to PAC1R, peptide induces EGFR phosphorylation via PKA-signaling cascade stimulation. EGFR trans-activation triggers MAPK/ERK signaling pathway involved in cell survival and proliferation. In conclusion, data have suggested that PACAP-38 acts through EGFR phosphorylation in DR and this effect particularly occurs on RPE layer.
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Affiliation(s)
- Grazia Maugeri
- Section of Human Anatomy and Histology, Department of Biomedical and Biotechnological Sciences, University of Catania, Italy
| | - Agata Grazia D'Amico
- San Raffaele Open University of Rome, Department of Human Science and Promotion of quality of Life, Italy
| | - Claudio Bucolo
- Section of Pharmacology, Department of Biomedical and Biotechnological Sciences, University of Catania, Italy; Center for Research in Ocular Pharmacology - CERFO, Department of Biomedical and Biotechnological Sciences, University of Catania, Italy
| | - Velia D'Agata
- Section of Human Anatomy and Histology, Department of Biomedical and Biotechnological Sciences, University of Catania, Italy.
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18
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Li D, Liu GQ, Lu PR. High glucose: activating autophagy and affecting the biological behavior of human lens epithelial cells. Int J Ophthalmol 2019; 12:1061-1066. [PMID: 31341793 DOI: 10.18240/ijo.2019.07.02] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2018] [Accepted: 10/22/2018] [Indexed: 02/06/2023] Open
Abstract
AIM To clarify the effect of autophagy on human lens epithelial cells (HLECs) under high glucose conditions. METHODS HLECs were cultured with different concentrations of glucose and 3-methyladenine (3-MA); the expression of autophagy-related protein LC3B was detected by Western blotting and immunofluorescence histochemistry. The migration of HLECs was quantified by scratch wound assay and the expression of transforming growth factor-β (TGF-β) was measured by real-time polymerase chain reaction. RESULTS Compared with 5 mmol/L normal glucose treatment, 40 mmol/L glucose treatment can significantly increase the generation of autophagosome in HLECs, which could be inhibited by 0.375 mmol/L 3-MA treatment. The migration of HLECs and the expression of TGF-β in HLECs induced by high glucose were significantly suppressed by 0.375 mmol/L 3-MA treatment. CONCLUSION Autophagy promotes HLECs cell migration and increases the expression of TGF-β after exposed to high glucose, which may relate to the development of diabetic cataract.
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Affiliation(s)
- Dan Li
- Department of Ophthalmology, the First Affiliated Hospital of Soochow University, Suzhou 215006, Jiangsu Province, China
| | - Gao-Qin Liu
- Department of Ophthalmology, the First Affiliated Hospital of Soochow University, Suzhou 215006, Jiangsu Province, China
| | - Pei-Rong Lu
- Department of Ophthalmology, the First Affiliated Hospital of Soochow University, Suzhou 215006, Jiangsu Province, China
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19
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Chen P, Miao Y, Yan P, Wang XJ, Jiang C, Lei Y. MiR-455-5p ameliorates HG-induced apoptosis, oxidative stress and inflammatory via targeting SOCS3 in retinal pigment epithelial cells. J Cell Physiol 2019; 234:21915-21924. [PMID: 31041827 DOI: 10.1002/jcp.28755] [Citation(s) in RCA: 33] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2019] [Revised: 03/29/2019] [Accepted: 04/11/2019] [Indexed: 12/19/2022]
Abstract
Diabetic retinopathy (DR) remains the leading cause of blindness in adults with diabetes mellitus. Numerous microRNAs (miRNAs) have been identified to modulate the pathogenesis of DR. The main purpose of this study was to evaluate the potential roles of miR-455-5p in high glucose (HG)-treated retinal pigment epithelial (RPE) cells and underlying mechanisms. Our present investigation discovered that the expression of miR-455-5p was apparently downregulated in ARPE-19 cells stimulated with HG. In addition, forced expression of miR-455-5p markedly enhanced cell viability and restrained HG-induced apoptosis accompanied by decreased BCL2-associated X protein (Bax)/B-cell leukemia/lymphoma 2 (Bcl-2) ratio and expression of apoptotic marker cleaved caspase-3 during HG challenged. Subsequently, augmentation of miR-455-5p remarkably alleviated HG-triggered oxidative stress injury as reflected by decreased the production of intracellular reactive oxygen species (ROS) and malondialdehyde (MDA) content as well as NADPH oxidase 4 expression, concomitant with enhanced the activities of superoxide dismutase, catalase, and GPX stimulated with HG. Furthermore, enforced expression of miR-455-5p effectively ameliorated HG-stimulated inflammatory response as exemplified by repressing the secretion of inflammatory cytokines interleukin 1β (IL-1β), IL-6, and tumour necrosis factor-α in ARPE-19 cells challenged by HG. Most importantly, we successfully identified suppressor of cytokine signaling 3 (SOCS3) as a direct target gene of miR-455-5p, and miR-455-5p negatively regulated the expression of SOCS3. Mechanistically, restoration of SOCS3 abrogated the beneficial effects of miR-455-5p on apoptosis, accumulation of ROS, and inflammatory factors production in response to HG. Taken together, these findings demonstrated that miR-455-5p relieved HG-induced damage through repressing apoptosis, oxidant stress, and inflammatory response by targeting SOCS3. The study gives evidence that miR-455-5p may serve as a new potential therapeutic agent for DR treatment.
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Affiliation(s)
- Pan Chen
- Department of Endocrinology and Metabolism, The Affiliated Hospital of Southwest Medical University, Luzhou, Sichuan, People's Republic of China
| | - Ying Miao
- Department of Endocrinology and Metabolism, The Affiliated Hospital of Southwest Medical University, Luzhou, Sichuan, People's Republic of China
| | - PuJun Yan
- Department of Endocrinology and Metabolism, The Affiliated Hospital of Southwest Medical University, Luzhou, Sichuan, People's Republic of China
| | - Xiao Jie Wang
- Department of Endocrinology and Metabolism, The Affiliated Hospital of Southwest Medical University, Luzhou, Sichuan, People's Republic of China
| | - ChunXia Jiang
- Department of Endocrinology and Metabolism, The Affiliated Hospital of Southwest Medical University, Luzhou, Sichuan, People's Republic of China
| | - Yi Lei
- Department of Endocrinology and Metabolism, The Affiliated Hospital of Southwest Medical University, Luzhou, Sichuan, People's Republic of China
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Wang N, Zou C, Zhao S, Wang Y, Han C, Zheng Z. Fenofibrate Exerts Protective Effects in Diabetic Retinopathy via Inhibition of the ANGPTL3 Pathway. Invest Ophthalmol Vis Sci 2019; 59:4210-4217. [PMID: 30128492 DOI: 10.1167/iovs.18-24155] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
Purpose Fenofibrate has been demonstrated to exert a promising therapeutic effect against diabetic retinopathy. Angiopoietin-like 3 (ANGPTL3) has been shown to exert significant pathogenic effects on vascular endothelial cells, which are critically involved in the pathogenesis of diabetic retinopathy. The present study aimed to investigate the link between the therapeutic effects of fenofibrate and the pathogenic effects of ANGPTL3 in diabetic retinopathy. Methods Diabetic and control rats were randomly assigned to the following treatments: intravitreal injection with ANGPTL3 small interfering RNA (siRNA), recombinant human (rh)ANGPTL3, fed with normal feeds, or fenofibrate-containing feeds for 8 weeks. Human retinal microvascular endothelial cells (HRMECs) were exposed to normal glucose or high glucose levels with ANGPTL3 siRNA, ANGPTL3 RNA overexpression, blank vector, cilengitide, or fenofibrate treatment. Expression levels of ANGPTL3, IL-1, IL-6, Bax, P53, VEGF, and integrin αVβ3 in the retinas of rats and HRMECs were examined by Western blotting and real-time PCR. The apoptosis rates of HRMECs were examined using a TUNEL apoptosis assay kit. Results Expression levels of ANGPTL3, IL-1β, IL-6, Bax, P53, VEGF, and integrin αVβ3 were found to be upregulated after high-glucose stimulation or ANGPTL3 overexpression in HRMECs or diabetic retinal tissue. However, expression levels of the above markers were downregulated following fenofibrate intervention, blockage of integrin αVβ3 receptor, or ANGPTL3 siRNA interference. Conclusions We identified fenofibrate exerts its protective effects by inhibiting ANGPTL3-induced apoptosis and inflammation in diabetic retinopathy, which is a novel mechanism.
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Affiliation(s)
- Na Wang
- Department of Ophthalmology, Shanghai First People's Hospital, Shanghai Jiao Tong University, Shanghai, People's Republic of China
| | - Chen Zou
- Department of Ophthalmology, Shanghai First People's Hospital, Shanghai Jiao Tong University, Shanghai, People's Republic of China
| | - Shuzhi Zhao
- Department of Ophthalmology, Shanghai First People's Hospital, Shanghai Jiao Tong University, Shanghai, People's Republic of China
| | - Yunzhi Wang
- Department of Ophthalmology, Shanghai First People's Hospital, Shanghai Jiao Tong University, Shanghai, People's Republic of China
| | - Changjing Han
- Department of Ophthalmology, Shanghai First People's Hospital, Shanghai Jiao Tong University, Shanghai, People's Republic of China
| | - Zhi Zheng
- Department of Ophthalmology, Shanghai First People's Hospital, Shanghai Jiao Tong University, Shanghai, People's Republic of China
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Wong M, Ganapathy AS, Suchanec E, Laidler L, Ma T, Nighot P. Intestinal epithelial tight junction barrier regulation by autophagy-related protein ATG6/beclin 1. Am J Physiol Cell Physiol 2019; 316:C753-C765. [PMID: 30892937 DOI: 10.1152/ajpcell.00246.2018] [Citation(s) in RCA: 35] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
A defective tight junction (TJ) barrier is a key pathogenic factor for inflammatory bowel disease. Previously, we have shown that autophagy, a cell survival mechanism, enhances intestinal epithelial TJ barrier function. Autophagy-related protein-6 (ATG6/beclin 1), a key protein in the autophagy pathway, also plays a role in the endocytic pathway. The constitutive role of beclin 1 in the intestinal TJ barrier is not known. In Caco-2 cells, beclin 1 was found to be coimmunoprecipitated with the TJ protein occludin and colocalized with occludin on the membrane. Treatment of Caco-2 cells with beclin 1 peptide [transactivating regulatory protein (Tat)-beclin 1] reduced TJ barrier function. Activation of beclin 1 increased occludin endocytosis and reduced total occludin protein level. In contrast, beclin 1 siRNA transfection enhanced Caco-2 TJ barrier function. In pharmacologic and genetic autophagy inhibition studies, the constitutive function of beclin 1 in the TJ barrier was found to be autophagy independent. However, de novo induction of autophagy with starvation or rapamycin prevented Tat-beclin 1-induced increase in TJ permeability and reduction in occludin level. Induction of autophagy also resulted in reduced beclin 1-occludin association. In mouse colon, beclin 1 colocalized with occludin on the epithelial membrane. Perfusion of mouse colon with beclin 1 peptide caused an increase in colonic TJ permeability that was prevented by in vivo induction of autophagy. These findings show that beclin 1 plays a constitutive, autophagy-independent role in the regulation of intestinal TJ barrier function via endocytosis of occludin. Autophagy terminates constitutive beclin 1 function in the TJ barrier and enhances the TJ barrier.
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Affiliation(s)
- Morgan Wong
- Department of Internal Medicine, University of New Mexico School of Medicine , Albuquerque, New Mexico
| | | | - Eric Suchanec
- Department of Medicine, College of Medicine, Pennsylvania State University , Hershey, Pennsylvania
| | - Laura Laidler
- Department of Internal Medicine, University of New Mexico School of Medicine , Albuquerque, New Mexico
| | - Thomas Ma
- Department of Medicine, College of Medicine, Pennsylvania State University , Hershey, Pennsylvania
| | - Prashant Nighot
- Department of Medicine, College of Medicine, Pennsylvania State University , Hershey, Pennsylvania
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22
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Li J, Wang P, Chen Z, Yu S, Xu H. Fenofibrate Ameliorates Oxidative Stress-Induced Retinal Microvascular Dysfunction in Diabetic Rats. Curr Eye Res 2018; 43:1395-1403. [PMID: 30024319 DOI: 10.1080/02713683.2018.1501072] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Affiliation(s)
- Jun Li
- Department of Ophthalmology, Lishui Municipal Central Hospital, The Fifth Affiliated Hospital of Wenzhou Medical University, Lishui, PR China
- Department of Ophthalmology, Lishui Hospital, Zhejiang University School of Medicine, Lishui, PR China
| | - Peipei Wang
- Department of Ophthalmology, Lishui Municipal Central Hospital, The Fifth Affiliated Hospital of Wenzhou Medical University, Lishui, PR China
- Department of Ophthalmology, Lishui Hospital, Zhejiang University School of Medicine, Lishui, PR China
- Department of Stomatology, Lishui Hospital, Zhejiang University School of Medicine, Lishui, PR China
| | - Zhen Chen
- Department of Ophthalmology, Lishui Municipal Central Hospital, The Fifth Affiliated Hospital of Wenzhou Medical University, Lishui, PR China
- Department of Ophthalmology, Lishui Hospital, Zhejiang University School of Medicine, Lishui, PR China
| | - Songping Yu
- Department of Ophthalmology, Lishui Municipal Central Hospital, The Fifth Affiliated Hospital of Wenzhou Medical University, Lishui, PR China
- Department of Ophthalmology, Lishui Hospital, Zhejiang University School of Medicine, Lishui, PR China
| | - Huiwen Xu
- Department of Ophthalmology, Lishui Municipal Central Hospital, The Fifth Affiliated Hospital of Wenzhou Medical University, Lishui, PR China
- Department of Ophthalmology, Lishui Hospital, Zhejiang University School of Medicine, Lishui, PR China
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23
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Tao T, Zhao F, Xuan Q, Shen Z, Xiao J, Shen Q. Fenofibrate inhibits the growth of prostate cancer through regulating autophagy and endoplasmic reticulum stress. Biochem Biophys Res Commun 2018; 503:2685-2689. [PMID: 30098788 DOI: 10.1016/j.bbrc.2018.08.024] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2018] [Accepted: 08/03/2018] [Indexed: 12/15/2022]
Abstract
Fenofibrate is a fibric acid derivative which exhibits a role of peroxisome proliferator-activated receptor-alpha agonist. It is widely utilized in therapy of hyperlipidemia and hypercholesterolemia. Its anticancer function is discovered in recent years. However, the role of fenofibrate in prostate cancer (PCa) is poorly understood. In this study, we investigated the function and mechanism of fenofibrate in PCa cells. Firstly, fenofibrate treated PCa cells showed more apoptosis compared with the control group. Further, we found that fenofibrate induced autophagy but finally blocked its complete flux in PCa cells through regulating AMPK-mTOR pathway. The intermediate metabolite from uncompleted autophagy induced endoplasmic reticulum stress (ER stress) via PERK and IRE1 signalings. In vivo mice model confirmed that fenofibrate inhibited the growth of PCa. This study suggests that fenofibrate is an effective inhibitor of PCa by regulating autophagy and ER stress.
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Affiliation(s)
- Tao Tao
- Department of Urology, The First Affiliated Hospital of USTC, Division of Life Sciences and Medicine, University of Science and Technology of China, Hefei, Anhui, 230001, PR China
| | - Fenglun Zhao
- Department of Pharmacy, The Second Affiliated Hospital of Soochow University, Suzhou, Jiangsu, 215004, PR China
| | - Qiang Xuan
- Department of Urology, The First Affiliated Hospital of USTC, Division of Life Sciences and Medicine, University of Science and Technology of China, Hefei, Anhui, 230001, PR China
| | - Zhou Shen
- Department of Urology, The First Affiliated Hospital of USTC, Division of Life Sciences and Medicine, University of Science and Technology of China, Hefei, Anhui, 230001, PR China
| | - Jun Xiao
- Department of Urology, The First Affiliated Hospital of USTC, Division of Life Sciences and Medicine, University of Science and Technology of China, Hefei, Anhui, 230001, PR China.
| | - Qi Shen
- Department of Radiation Oncology, The First Affiliated Hospital of USTC, Division of Life Sciences and Medicine, University of Science and Technology of China, Hefei, Anhui, 230001, PR China.
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24
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Bhattacharya D, Mukhopadhyay M, Bhattacharyya M, Karmakar P. Is autophagy associated with diabetes mellitus and its complications? A review. EXCLI JOURNAL 2018; 17:709-720. [PMID: 30190661 PMCID: PMC6123605 DOI: 10.17179/excli2018-1353] [Citation(s) in RCA: 31] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/21/2018] [Accepted: 07/11/2018] [Indexed: 02/06/2023]
Abstract
Diabetes mellitus (DM) is an endocrine disorder. In coming decades it will be one of the leading causes of death globally. The key factors in the pathogenesis of diabetes are cellular injuries and disorders of energy metabolism leading to severe diabetic complications. Recent studies have confirmed that autophagy plays a pivotal role in diabetes and its complications. It has been observed that autophagy regulates the normal function of pancreatic β cells and insulin-target tissues, such as skeletal muscle, liver, and adipose tissue. This review will summarize the regulation of autophagy in diabetes and its complications, and explore how this process would emerge as a potential therapeutic target for diabetes treatment.
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Affiliation(s)
- Debalina Bhattacharya
- Department of Biochemistry, University of Calcutta, Kolkata-700019
- Department of Life Science and Biotechnology, Jadavpur University, Kolkata-700032
| | | | | | - Parimal Karmakar
- Department of Life Science and Biotechnology, Jadavpur University, Kolkata-700032
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25
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Huang C, Lu H, Xu J, Yu H, Wang X, Zhang X. Protective roles of autophagy in retinal pigment epithelium under high glucose condition via regulating PINK1/Parkin pathway and BNIP3L. Biol Res 2018; 51:22. [PMID: 30012208 PMCID: PMC6047129 DOI: 10.1186/s40659-018-0169-4] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2018] [Accepted: 06/06/2018] [Indexed: 12/11/2022] Open
Abstract
Background Our study aimed to investigate the roles of autophagy against high glucose induced response in retinal pigment epithelium (ARPE-19 cells). Methods The morphological changes and reactive oxygen species (ROS) generation in ARPE-19 cells under high glucose treatment were respectively detected using the transmission electron microscopy and flow cytometry. The expression levels of Parkin, PINK1, BNIP3L, LC3-I and LC3-II in ARPE-19 cells received high glucose treatment were measured by western blot after pretreatment of carbonyl cyanide m-chlorophenylhydrazone (CCCP), 3-methyladenine (3-MA), N-acetyl cysteine (NAC) or cyclosporin A (CsA) followed by high glucose treatment. Results ARPE-19 cells subjected to high glucose stress showed an obvious reduction in the LC3-I expression and significant increase in the number of autophagosomes, in the intracellular ROS level, and in the expression levels of Parkin, PINK1, BNIP3L and LC3-II (p < 0.05). Pretreatment with CCCP significantly reduced the LC3-I expression and increased the expression levels of Parkin, PINK1, BNIP3L and LC3-II (p < 0.05). ARPE-19 cells pretreated with CsA under high glucose stress showed markedly down-regulated expressions of Parkin, PINK1 and BNIP3L compared with the cells treated with high glucose (p < 0.05). Pretreatment of ARPE-19 cells with NAC or 3-MA under high glucose stress resulted in a marked reduction in the expression levels of PINK1, BNIP3L and LC3-II (p < 0.05). Meanwhile, the expression level of Parkin in the ARPE-19 cells pretreated with NAC under high glucose stress was comparable with that in the control cells. Conclusion Autophagy might have protective roles against high glucose induced injury in ARPE19 cells via regulating PINK1/Parkin pathway and BNIP3L.
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Affiliation(s)
- Chengchi Huang
- Ophthalmology Hospital, The First Affiliated Hospital of Harbin Medical University, 23 Youzheng Street, Nangang District, Harbin, 150001, China.,Department of Ophthalmology, The Fourth Affiliated Hospital, Harbin Medical University, 17 Yiyuan Street, Nangang District, Harbin, 150001, China
| | - Hong Lu
- Ophthalmology Hospital, The First Affiliated Hospital of Harbin Medical University, 23 Youzheng Street, Nangang District, Harbin, 150001, China
| | - Junyu Xu
- Ophthalmology Hospital, The First Affiliated Hospital of Harbin Medical University, 23 Youzheng Street, Nangang District, Harbin, 150001, China
| | - Hongmin Yu
- Ophthalmology Hospital, The First Affiliated Hospital of Harbin Medical University, 23 Youzheng Street, Nangang District, Harbin, 150001, China
| | - Xiaodan Wang
- Ophthalmology Hospital, The First Affiliated Hospital of Harbin Medical University, 23 Youzheng Street, Nangang District, Harbin, 150001, China
| | - Xiaomei Zhang
- Ophthalmology Hospital, The First Affiliated Hospital of Harbin Medical University, 23 Youzheng Street, Nangang District, Harbin, 150001, China.
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26
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Harmer JA, Keech AC, Veillard AS, Skilton MR, Watts GF, Celermajer DS. Fenofibrate effects on carotid artery intima-media thickness in adults with type 2 diabetes mellitus: A FIELD substudy. Diabetes Res Clin Pract 2018; 141:156-167. [PMID: 29763709 DOI: 10.1016/j.diabres.2018.05.006] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/19/2018] [Revised: 04/16/2018] [Accepted: 05/08/2018] [Indexed: 11/16/2022]
Abstract
AIM Dyslipidemia in type 2 diabetes contributes to an increased risk of cardiovascular disease. Fenofibrate, a lipid-regulating peroxisome proliferator-activated receptor-α (PPARα) agonist, has been shown to reduce vascular complications in adults with type 2 diabetes. The mechanisms for such benefit, however, are not yet well understood. We examined the effects of fenofibrate on carotid intima-media thickness (IMT), a marker of subclinical atherosclerosis, in adults with type 2 diabetes. METHODS In a prospectively designed substudy of the Fenofibrate Intervention and Event Lowering in Diabetes (FIELD) study, we assessed carotid IMT in a subset of 422 representative adults. Traditional risk factors and IMT were assessed at 2 and 4 years after randomisation to fenofibrate (200 mg daily) or placebo. The prespecified primary study endpoint was the difference in IMT between treatment groups at 4 years. Post-hoc analyses were performed according to dyslipidemia and metabolic syndrome status. RESULTS There was no difference in carotid IMT comparing those assigned to fenofibrate or placebo at 2 or 4 years, despite statistically significant improvement in lipid and lipoprotein parameters at 2 and 4 years, including TC, LDL-C and TG, and HDL-C at 4 months and 2 years. Similarly, there was no difference in carotid IMT on fenofibrate compared with placebo in those with dyslipidemia or metabolic syndrome. CONCLUSIONS Fenofibrate was not associated with improved carotid IMT in adults with type 2 diabetes when compared with placebo, despite a statistically significant improvement in TC, LDL-C and TG at 2 and 4 years, and HDL-C at 4 months and 2 years.
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Affiliation(s)
- Jason A Harmer
- Sydney Medical School, University of Sydney, Sydney, NSW, Australia; Department of Cardiology, Royal North Shore Hospital, Sydney, NSW, Australia; Faculty of Medicine, Western Sydney University, Sydney, NSW, Australia.
| | - Anthony C Keech
- Sydney Medical School, University of Sydney, Sydney, NSW, Australia; Department of Cardiology, Royal Prince Alfred Hospital, Sydney, NSW, Australia; NHMRC Clinical Trials Center, University of Sydney, Sydney, NSW, Australia
| | | | - Michael R Skilton
- Sydney Medical School, University of Sydney, Sydney, NSW, Australia; Department of Cardiology, Royal Prince Alfred Hospital, Sydney, NSW, Australia
| | - Gerald F Watts
- Lipid Disorders Clinic, Department of Cardiology, Royal Perth Hospital, Perth, WA, Australia; School of Medicine and Pharmacology, University of Western Australia, Perth, WA, Australia
| | - David S Celermajer
- Sydney Medical School, University of Sydney, Sydney, NSW, Australia; Department of Cardiology, Royal Prince Alfred Hospital, Sydney, NSW, Australia
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27
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Srinivasan S, Hande P, Shetty J, Murali S. Efficiency of fenofibrate in facilitating the reduction of central macular thickness in diabetic macular edema. Indian J Ophthalmol 2018; 66:98-105. [PMID: 29283132 PMCID: PMC5778593 DOI: 10.4103/ijo.ijo_566_17] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022] Open
Abstract
PURPOSE The purpose of this study is to study the benefit of addition of oral fenofibrate to the current regimen of diabetic macular edema (DME) management and quantify its effect on macular thickness and visual function in DME. METHODS Fifty-three eyes of 50 patients were randomized into treatment (Group A) (oral fenofibrate 160 mg/day) and control groups (Group B). Both groups underwent treatment of DME as per the standard treatment protocol of our hospital including intravitreal injections (anti-vascular endothelial growth factor/steroid) and grid laser. Patients were followed up every 2 months to note the visual acuity and central macular thickness (CMT) for 6 months. RESULTS Our groups were matched with respect to age (P = 0.802), mean diabetic age (P = 0.878), serum HbA1C levels (P = 0.523), and serum triglyceride levels (P = 0.793). The mean reduction in CMT was 136 μ in Group A and 83 μ in Group B at the end of 6 months. This difference was statistically significant (P = 0.031). Visual acuity improvement was 0.15 in Group A and 0.11 in Group B at the end of 6 months (P = 0.186). On subgroup analysis in Group A, we found that there was no difference in reduction of CMT between hypertensives and normotensives (P = 0.916), in patients with normal triglyceride levels and increased triglyceride levels (P = 0.975). CONCLUSION Addition of fenofibrate to the standard protocol of DME management seems to facilitate reduction of CMT and probably have an added benefit on the visual functions.
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Affiliation(s)
- Srilakshmi Srinivasan
- Department of Vitreo Retina, Bangalore West Lions Super Speciality Eye Hospital, Bengaluru, Karnataka, India
| | - Prathibha Hande
- Department of Vitreo Retina, Bangalore West Lions Super Speciality Eye Hospital, Bengaluru, Karnataka, India
| | - Jyoti Shetty
- Department of Vitreo Retina, Bangalore West Lions Super Speciality Eye Hospital, Bengaluru, Karnataka, India
| | - Sindhu Murali
- Department of Vitreo Retina, Bangalore West Lions Super Speciality Eye Hospital, Bengaluru, Karnataka, India
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28
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Liu WY, Liou SS, Hong TY, Liu IM. The Benefits of the Citrus Flavonoid Diosmin on Human Retinal Pigment Epithelial Cells under High-Glucose Conditions. Molecules 2017; 22:molecules22122251. [PMID: 29258224 PMCID: PMC6149669 DOI: 10.3390/molecules22122251] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2017] [Revised: 12/02/2017] [Accepted: 12/08/2017] [Indexed: 12/22/2022] Open
Abstract
We investigate diosmin for its effect on the ARPE-19 human retinal pigment epithelial cells exposed to high glucose, a model of diabetic retinopathy (DR). After incubation for 4 days with a normal (5 mmol/L) concentration of D-glucose, ARPE-19 cells were exposed separately to normal or high concentrations of D-glucose (30 mmol/L) with or without diosmin at different concentrations (0.1, 1, 10 μg/mL) for another 48 h. Next, we assessed cell viability, reactive oxygen species (ROS) generation and antioxidant enzyme activities. In order to examine the underlying molecular mechanisms, we meanwhile analyzed the expressions of Bax, Bcl-2, total and phosphorylated JNK and p38 mitogen-activated protein kinase (MAPK). Diosmin dose dependently enhanced cell viability following high glucose treatment in ARPE-19 cells. The activities of superoxide dismutase and glutathione peroxidase, as well as the levels of reduced glutathione were decreased, while it was observed that levels of ROS in high glucose cultured ARPE-19 cells increased. High glucose also disturbed Bax and Bcl-2 expression, interrupted Bcl-2/Bax balance, and triggered subsequent cytochrome c release into the cytosol and activation of caspase-3. These detrimental effects were ameliorated dose dependently by diosmin. Furthermore, diosmin could abrogate high glucose-induced apoptosis as well as JNK and P38 MAPK phosphorylation in ARPE-19 cells. Our results suggest that treatment ARPE-19 cells with diosmin halts hyperglycemia-mediated oxidative damage and thus this compound may be a candidate for preventing the visual impairment caused by DR.
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Affiliation(s)
- Wayne Young Liu
- Department of Urology, Jen-Ai Hospital, Taichung City 41625, Taiwan.
- Center for Basic Medical Science, College of Health Science, Central Taiwan University of Science and Technology, Taichung City 40601, Taiwan.
| | - Shorong-Shii Liou
- Department of Pharmacy and Master Program, College of Pharmacy and Health Care, Tajen University, Pingtung County 90741, Taiwan.
| | - Tang-Yao Hong
- Department of Biotechnology, College of Pharmacy and Health Care, Tajen University, Pingtung County 90741, Taiwan.
| | - I-Min Liu
- Department of Pharmacy and Master Program, College of Pharmacy and Health Care, Tajen University, Pingtung County 90741, Taiwan.
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29
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Liao R, Yan F, Zeng Z, Wang H, Qiu K, Xu J, Zheng W. Insulin-like growth factor-1 activates PI3K/Akt signalling to protect human retinal pigment epithelial cells from amiodarone-induced oxidative injury. Br J Pharmacol 2017; 175:125-139. [PMID: 29057462 DOI: 10.1111/bph.14078] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2016] [Revised: 10/11/2017] [Accepted: 10/13/2017] [Indexed: 12/21/2022] Open
Abstract
BACKGROUND AND PURPOSE Amiodarone is one of the most effective anti-arrhythmic drugs available, but its clinical applications are limited by toxic side effects including optic toxicity. The purpose of this study was to investigate the toxic effect of amiodarone on D407 cells (a human retinal pigmented epithelial (RPE) cell line) and the mechanisms of the protective effect of insulin-like growth factor-1 (IGF-1). EXPERIMENTAL APPROACH The involvement of the kinases, Akt and ERK, was analysed by Western blot. Intracellular accumulation of ROS was measured using fluorophotometric quantification. A pharmacological approach with inhibitors was used to investigate the pathways involved in the protective action of IGF-1. KEY RESULTS Amiodarone concentration-dependently augmented the production of ROS, lipid peroxidation and apoptosis in D407 cells. IGF-1 time- and concentration-dependently reversed these effects of amiodarone and protected D407 cells from amiodarone-mediated toxicity. Amiodarone inhibited the pAkt but not pErk, and IGF-1 reversed this inhibitory effect of amiodarone. However, IGF-1 failed to suppress amiodarone-induced cytotoxicity in the presence of PI3K/Akt inhibitor LY294002 suggesting the direct involvement of the PI3K/Akt pathway. Furthermore, in vivo rat flash electroretinogram (FERG) recordings showed that IGF-1 reverses the amiodarone-induced decrease in a- and b-waves. The immunocytochemistry findings confirmed that vitreous IGF-1 injections promote the survival of RPE cells in rat retina treated with amiodarone. CONCLUSION AND IMPLICATIONS IGF-1 can protect RPE cells from amiodarone-mediated injury via the PI3K/Akt pathway in vivo and in vitro. IGF-1 has potential as a protective drug for the prevention and treatment of amiodarone-induced optic toxicity.
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Affiliation(s)
- Rifang Liao
- Faculty of Health Sciences, University of Macau, Taipa, Macau, and UM Zhuhai Research Institute, Zhuhai, China.,Department of Pharmacy, Sun Yat-Sen Memorial Hospital and the School of Pharmaceutical Sciences, Sun Yat-sen University, Guangzhou, China
| | - Fengxia Yan
- Faculty of Health Sciences, University of Macau, Taipa, Macau, and UM Zhuhai Research Institute, Zhuhai, China.,Department of Pharmacy, Sun Yat-Sen Memorial Hospital and the School of Pharmaceutical Sciences, Sun Yat-sen University, Guangzhou, China
| | - Zhuanping Zeng
- School of Public Health, Guangdong Pharmaceutical University, Guangzhou, China
| | - Haitao Wang
- Faculty of Health Sciences, University of Macau, Taipa, Macau, and UM Zhuhai Research Institute, Zhuhai, China.,School of Pharmaceutical Sciences, Southern Medical University, Guangzhou, China
| | - Kaifeng Qiu
- Department of Pharmacy, Sun Yat-Sen Memorial Hospital and the School of Pharmaceutical Sciences, Sun Yat-sen University, Guangzhou, China
| | - Jinying Xu
- Faculty of Health Sciences, University of Macau, Taipa, Macau, and UM Zhuhai Research Institute, Zhuhai, China
| | - Wenhua Zheng
- Faculty of Health Sciences, University of Macau, Taipa, Macau, and UM Zhuhai Research Institute, Zhuhai, China.,Department of Pharmacy, Sun Yat-Sen Memorial Hospital and the School of Pharmaceutical Sciences, Sun Yat-sen University, Guangzhou, China
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30
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Ma JH, Wang JJ, Li J, Pfeffer BA, Zhong Y, Zhang SX. The Role of IRE-XBP1 Pathway in Regulation of Retinal Pigment Epithelium Tight Junctions. Invest Ophthalmol Vis Sci 2017; 57:5244-5252. [PMID: 27701635 PMCID: PMC5054729 DOI: 10.1167/iovs.16-19232] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023] Open
Abstract
Purpose The retinal pigment epithelium (RPE) tight junctions play a pivotal role in maintaining the homeostatic environment of the neural retina. Herein, we investigated the role of X-box binding protein 1 (XBP1), an endoplasmic reticulum (ER) stress-responsive transcription factor, in regulation of RPE tight junctions. Methods Human RPE cell line (ARPE-19) and primary primate RPE cells were used for in vitro experiments and RPE-specific XBP1 knockout (KO) mice were used for in vivo study. Endoplasmic reticulum stress was induced by a sublethal dose of thapsigargin or tunicamycin. XBP1 activation was manipulated by IRE inhibitor 4μ8C, which suppresses XBP1 mRNA splicing. The integrity of tight junctions and the involvement of calcium-dependent RhoA/Rho kinase pathway were examined. Results Induction of ER stress by thapsigargin, but not tunicamycin, disrupted RPE tight junctions in ARPE-19 cells. Inhibition of XBP1 activation by 4μ8C resulted in a remarkable downregulation of tight junction proteins (ZO-1 and occludin) and defects in tight junction formation in the presence or absence of ER stress inducers. Overexpression of active XBP1 partially reversed 4μ8C-induced anomalies in tight junctions. Mechanistically, XBP1 inhibition resulted in increased intracellular Ca2+ concentration, upregulation of RhoA expression, redistribution of F-actin, and tight junction damage, which was attenuated by Rho kinase inhibitor Y27632. In vivo, deletion of XBP1 in the RPE resulted in defective RPE tight junctions accompanied by increased VEGF expression. Conclusions Taken together, these results suggest a protective role of XBP1 in maintaining RPE tight junctions possibly through regulation of calcium-dependent RhoA/Rho kinase signaling and actin cytoskeletal reorganization.
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Affiliation(s)
- Jacey H Ma
- Departments of Ophthalmology and Biochemistry, University at Buffalo, State University of New York, Buffalo, New York, United States 2SUNY Eye Institute, State University of New York, New York, United States 3Aier School of Ophthalmology, Central South University, Changsha, Hunan, China
| | - Joshua J Wang
- Departments of Ophthalmology and Biochemistry, University at Buffalo, State University of New York, Buffalo, New York, United States 2SUNY Eye Institute, State University of New York, New York, United States
| | - Junhua Li
- Departments of Ophthalmology and Biochemistry, University at Buffalo, State University of New York, Buffalo, New York, United States 2SUNY Eye Institute, State University of New York, New York, United States
| | - Bruce A Pfeffer
- Departments of Ophthalmology and Biochemistry, University at Buffalo, State University of New York, Buffalo, New York, United States 2SUNY Eye Institute, State University of New York, New York, United States 4Research Service, Veterans Administration Western New York Healthcare System, Buffalo, New York, United States
| | - Yiming Zhong
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou, Guangdong, China
| | - Sarah X Zhang
- Departments of Ophthalmology and Biochemistry, University at Buffalo, State University of New York, Buffalo, New York, United States 2SUNY Eye Institute, State University of New York, New York, United States
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Sheu SJ, Chen JL, Bee YS, Chen YA, Lin SH, Shu CW. Differential autophagic effects of vital dyes in retinal pigment epithelial ARPE-19 and photoreceptor 661W cells. PLoS One 2017; 12:e0174736. [PMID: 28358857 PMCID: PMC5373602 DOI: 10.1371/journal.pone.0174736] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2016] [Accepted: 03/14/2017] [Indexed: 12/22/2022] Open
Abstract
Indocyanine green (ICG) and brilliant blue G (BBG) are commonly used vital dyes to remove internal limiting membrane (ILM) in vitreoretinal surgery. The vital dyes have shown cytotoxic effects in ocular cells. Autophagy is a stress responsive pathway for either protecting cells or promoting cell death. However, the role of autophagy in ocular cells in response to the vital dyes remains unknown. In this study, we found that ICG and BBG reduced cell viability in both human retinal pigment epithelial ARPE-19 and mouse photoreceptor 661W cells. ICG and BBG induced lipidated GFP-LC3-II and LC3-II in ARPE-19 and 661W cells. Combination treatment with the autophagy inhibitor chloroquine indicated that ICG and BBG reduced autophagic flux in ARPE-19 cells, whereas the vital dyes induced autophagic flux in 661W cells. Moreover, genetic and pharmacological ablation of autophagy enhanced vital dyes-induced cytotoxicity in ocular cells. Dietary supplements, including resveratrol, lutein, and CoQ10, induced autophagy and diminished the cytotoxic effects of ICG and BBG in ocular cells. These results suggest that autophagy may protect ARPE-19 and 661W cells from vital dyes-induced damage.
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Affiliation(s)
- Shwu-Jiuan Sheu
- Department of Ophthalmology, Kaohsiung Veterans General Hospital, Kaohsiung, Taiwan
- School of Medicine, National Yang-Ming University, Taipei, Taiwan
| | - Jiunn-Liang Chen
- Department of Ophthalmology, Kaohsiung Veterans General Hospital, Kaohsiung, Taiwan
- School of Medicine, National Yang-Ming University, Taipei, Taiwan
- Department of Optometry, Chung Hwa University of Medical Technology, Tainan, Taiwan
| | - Youn-Shen Bee
- Department of Ophthalmology, Kaohsiung Veterans General Hospital, Kaohsiung, Taiwan
- Yuh-Ing Junior College of Health Care & Management, Kaohsiung, Taiwan
- National Defense Medical Center, Taipei, Taiwan
| | - Yi-An Chen
- Department of Ophthalmology, Kaohsiung Veterans General Hospital, Kaohsiung, Taiwan
| | - Shi-Han Lin
- Department of Medical Education and Research, Kaohsiung Veterans General Hospital, Kaohsiung, Taiwan
| | - Chih-Wen Shu
- Department of Medical Education and Research, Kaohsiung Veterans General Hospital, Kaohsiung, Taiwan
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Jiang X, Wei Y, Zhang T, Zhang Z, Qiu S, Zhou X, Zhang S. Effects of GSK2606414 on cell proliferation and endoplasmic reticulum stress-associated gene expression in retinal pigment epithelial cells. Mol Med Rep 2017; 15:3105-3110. [DOI: 10.3892/mmr.2017.6418] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2016] [Accepted: 01/17/2017] [Indexed: 11/06/2022] Open
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Ioannidou E, Tseriotis VS, Tziomalos K. Role of lipid-lowering agents in the management of diabetic retinopathy. World J Diabetes 2017; 8:1-6. [PMID: 28138358 PMCID: PMC5237812 DOI: 10.4239/wjd.v8.i1.1] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/13/2016] [Revised: 09/17/2016] [Accepted: 11/16/2016] [Indexed: 02/05/2023] Open
Abstract
Diabetic retinopathy affects a substantial proportion of patients with diabetes mellitus (DM) and is the leading cause of blindness in working-aged adults. Even though the incidence of diabetic retinopathy has declined in the last decades, its prevalence increased and is expected to rise further as a result of the increasing incidence of type 2 DM (T2DM) and the longer life expectancy of patients with DM. The pathogenesis of diabetic retinopathy is multifactorial. Some observational studies suggested an association between dyslipidemia and the development and progression of retinopathy in patients with DM but others did not confirm this association. Regarding lipid-lowering agents, studies that evaluated the role of statins in the management of these patients are mostly small and yielded discrepant results. Large randomized studies with statins in patients with T2DM showed no benefit of these agents on diabetic retinopathy but were not designed to address this effect. In contrast, both preclinical data and two large randomized controlled studies, the FIELD and the ACCORD trial, showed that fenofibrate delays the progression of diabetic retinopathy. Even though the mechanisms underpinning this favorable effect are not entirely clear, these findings suggest that fenofibrate might represent a useful tool for the management of diabetic retinopathy.
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Maugeri G, D'Amico AG, Saccone S, Federico C, Cavallaro S, D'Agata V. PACAP and VIP Inhibit HIF-1α-Mediated VEGF Expression in a Model of Diabetic Macular Edema. J Cell Physiol 2016; 232:1209-1215. [PMID: 27661459 DOI: 10.1002/jcp.25616] [Citation(s) in RCA: 47] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2016] [Accepted: 09/21/2016] [Indexed: 12/12/2022]
Abstract
Pituitary adenylate cyclase-activating polypeptide (PACAP) and vasoactive intestinal peptide (VIP) exert a protective role against retinal injuries, including diabetic macular edema (DME). The macular damage is induced by hyperglycemia, which damages vessels supplying blood to the retina and induces hypoxia. The microenvironmental changes stimulate the expression of hypoxia-inducible factors (HIFs), which promote the choroidal endothelial cell transmigration across the retinal pigmented epithelium (RPE) into neurosensory retina, where they proliferate into new vessels under stimulation of the vascular endothelial growth factor (VEGF). In the present study, we have investigated whether PACAP and VIP prevent retinal damage by modulating the expression of HIFs, VEGF, and its receptors. In accord to our hypothesis, we have shown that both peptides are able to significantly reduce HIF-1α and increase HIF-3α expression in ARPE-19 cells exposed to hyperglycemic/hypoxic insult. This effect is also related to a reduction of VEGF and its receptors expression. Moreover, both peptides also reduce the activation of p38 mitogen-activated protein kinase (MAPK), a pro-apoptotic signaling pathway, which is activated by VEGFR-1 and 2 receptors. In conclusion, our study has further elucidated the protective role performed by PACAP and VIP, against the harmful combined effect of hyperglycemia/hypoxia characterizing the DME microenvironment. J. Cell. Physiol. 232: 1209-1215, 2017. © 2016 Wiley Periodicals, Inc.
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Affiliation(s)
- Grazia Maugeri
- Section of Human Anatomy and Histology, Department of Biomedical and Biotechnological Sciences, University of Catania, Catania, Italy
| | - Agata Grazia D'Amico
- Section of Human Anatomy and Histology, Department of Biomedical and Biotechnological Sciences, University of Catania, Catania, Italy.,San Raffaele Telematic University of Rome, Rome, Italy
| | - Salvatore Saccone
- Section of Animal Biology, Department of Biological, Geological and Environmental Sciences, University of Catania, Catania, Italy
| | - Concetta Federico
- Section of Animal Biology, Department of Biological, Geological and Environmental Sciences, University of Catania, Catania, Italy
| | - Sebastiano Cavallaro
- Institute of Neurological Sciences, Italian National Research Council, Catania, Italy
| | - Velia D'Agata
- Section of Human Anatomy and Histology, Department of Biomedical and Biotechnological Sciences, University of Catania, Catania, Italy
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Farnoodian M, Halbach C, Slinger C, Pattnaik BR, Sorenson CM, Sheibani N. High glucose promotes the migration of retinal pigment epithelial cells through increased oxidative stress and PEDF expression. Am J Physiol Cell Physiol 2016; 311:C418-36. [PMID: 27440660 DOI: 10.1152/ajpcell.00001.2016] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2016] [Accepted: 07/18/2016] [Indexed: 12/11/2022]
Abstract
Defects in the outer blood-retinal barrier have significant impact on the pathogenesis of diabetic retinopathy and macular edema. However, the detailed mechanisms involved remain largely unknown. This is, in part, attributed to the lack of suitable animal and cell culture models, including those of mouse origin. We recently reported a method for the culture of retinal pigment epithelial (RPE) cells from wild-type and transgenic mice. The RPE cells are responsible for maintaining the integrity of the outer blood-retinal barrier whose dysfunction during diabetes has a significant impact on vision. Here we determined the impact of high glucose on the function of RPE cells. We showed that high glucose conditions resulted in enhanced migration and increased the level of oxidative stress in RPE cells, but minimally impacted their rate of proliferation and apoptosis. High glucose also minimally affected the cell-matrix and cell-cell interactions of RPE cells. However, the expression of integrins and extracellular matrix proteins including pigment epithelium-derived factor (PEDF) were altered under high glucose conditions. Incubation of RPE cells with the antioxidant N-acetylcysteine under high glucose conditions restored normal migration and PEDF expression. These cells also exhibited increased nuclear localization of the antioxidant transcription factor Nrf2 and ZO-1, reduced levels of β-catenin and phagocytic activity, and minimal effect on production of vascular endothelial growth factor, inflammatory cytokines, and Akt, MAPK, and Src signaling pathways. Thus high glucose conditions promote RPE cell migration through increased oxidative stress and expression of PEDF without a significant effect on the rate of proliferation and apoptosis.
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Affiliation(s)
- Mitra Farnoodian
- Department of Ophthalmology and Visual Sciences, University of Wisconsin School of Medicine and Public Health, Madison, Wisconsin
| | - Caroline Halbach
- Department of Ophthalmology and Visual Sciences, University of Wisconsin School of Medicine and Public Health, Madison, Wisconsin
| | - Cassidy Slinger
- Department of Ophthalmology and Visual Sciences, University of Wisconsin School of Medicine and Public Health, Madison, Wisconsin
| | - Bikash R Pattnaik
- Department of Ophthalmology and Visual Sciences, University of Wisconsin School of Medicine and Public Health, Madison, Wisconsin; McPherson Eye Research Institute, University of Wisconsin School of Medicine and Public Health, Madison, Wisconsin; and
| | - Christine M Sorenson
- Department of Pediatrics, University of Wisconsin School of Medicine and Public Health, Madison, Wisconsin; McPherson Eye Research Institute, University of Wisconsin School of Medicine and Public Health, Madison, Wisconsin; and
| | - Nader Sheibani
- Department of Ophthalmology and Visual Sciences, University of Wisconsin School of Medicine and Public Health, Madison, Wisconsin; McPherson Eye Research Institute, University of Wisconsin School of Medicine and Public Health, Madison, Wisconsin; and Biomedical Engineering, University of Wisconsin School of Medicine and Public Health, Madison, Wisconsin
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Sabanayagam C, Yip W, Ting DSW, Tan G, Wong TY. Ten Emerging Trends in the Epidemiology of Diabetic Retinopathy. Ophthalmic Epidemiol 2016; 23:209-22. [PMID: 27355693 DOI: 10.1080/09286586.2016.1193618] [Citation(s) in RCA: 88] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
PURPOSE Diabetes is a major public health problem affecting 415 million people worldwide. With the increasing prevalence of diabetes, diabetic retinopathy (DR) is emerging as the leading cause of avoidable blindness worldwide. METHODS We reviewed previous and recent literature to provide an overview of emerging trends on the burden, epidemiology, risk factors, and prevention of DR. RESULTS First, there is clear evidence of a global increase in the prevalence of diabetes. Second, there is a decline in the incidence of blindness due to DR, particularly in developed countries. Third, diabetic macular edema (DME) rather than proliferative diabetic retinopathy (PDR) is the increasingly common cause of visual impairment. Fourth, DR awareness remains patchy and low in most populations. Fifth, hyperglycemia remains the most consistent risk factor for DR in type 1 diabetes across different studies and populations. Sixth, in contrast, blood pressure is an important risk factor for DR in type 2 diabetes. Seventh, the relationship between dyslipidemia and DR remains unclear, with inconsistent results from different studies and trials. Eighth, the utility of predictive models incorporating multiple risk factors for assessing DR risk requires evaluation. Ninth, photographic screening of DR using tele-ophthalmology platforms is increasingly recognized as being feasible and cost-effective. Finally, DR prevention in low-resource settings cannot follow models developed in high-resource countries and requires different strategies. CONCLUSIONS The ten trends we observed in the current review may guide planning of public healthcare strategies for the management of DR and prevention of blindness.
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Affiliation(s)
- Charumathi Sabanayagam
- a Singapore Eye Research Institute, Singapore National Eye Centre , Singapore.,b Center for Quantitative Medicine, Duke-NUS Medical School , Singapore.,c Yong Loo Lin School of Medicine , National University of Singapore , Singapore
| | - WanFen Yip
- a Singapore Eye Research Institute, Singapore National Eye Centre , Singapore
| | - Daniel S W Ting
- a Singapore Eye Research Institute, Singapore National Eye Centre , Singapore
| | - Gavin Tan
- a Singapore Eye Research Institute, Singapore National Eye Centre , Singapore
| | - Tien Y Wong
- a Singapore Eye Research Institute, Singapore National Eye Centre , Singapore.,c Yong Loo Lin School of Medicine , National University of Singapore , Singapore.,d Ophthalmology and Visual Sciences Academic Clinical Program, Duke-NUS Medical School , Singapore
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Nighot P, Ma T. Role of autophagy in the regulation of epithelial cell junctions. Tissue Barriers 2016; 4:e1171284. [PMID: 27583189 DOI: 10.1080/21688370.2016.1171284] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2016] [Revised: 03/21/2016] [Accepted: 03/22/2016] [Indexed: 01/07/2023] Open
Abstract
Autophagy is a cell survival mechanism by which bulk cytoplasmic material, including soluble macromolecules and organelles, is targeted for lysosomal degradation. The role of autophagy in diverse cellular processes such as metabolic stress, neurodegeneration, cancer, aging, immunity, and inflammatory diseases is being increasingly recognized. Epithelial cell junctions play an integral role in the cell homeostasis via physical binding, regulating paracellular pathways, integrating extracellular cues into intracellular signaling, and cell-cell communication. Recent data indicates that cell junction composition is very dynamic. The junctional protein complexes are actively regulated in response to various intra- and extra-cellular clues by intracellular trafficking and degradation pathways. This review discusses the recent and emerging information on how autophagy regulates various epithelial cell junctions. The knowledge of autophagy regulation of epithelial junctions will provide further rationale for targeting autophagy in a wide variety of human disease conditions.
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Affiliation(s)
- Prashant Nighot
- Department of Internal Medicine, University of New Mexico School of Medicine , Albuquerque, NM, USA
| | - Thomas Ma
- Department of Internal Medicine, University of New Mexico School of Medicine, Albuquerque, NM, USA; Veterans Affairs Medical Center, Albuquerque, NM, USA
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Fenofibrate increases cardiac autophagy via FGF21/SIRT1 and prevents fibrosis and inflammation in the hearts of Type 1 diabetic mice. Clin Sci (Lond) 2016; 130:625-41. [PMID: 26795437 DOI: 10.1042/cs20150623] [Citation(s) in RCA: 125] [Impact Index Per Article: 15.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2015] [Accepted: 01/21/2016] [Indexed: 02/02/2023]
Abstract
Fenofibrate (FF) as a commonly-used lipid-lowering medicine in clinics was examined for its potentially repurposing to prevent the cardiac abnormalities in patients with type 1 diabetes. We demonstrated here that fenofibrate significantly prevented diabetes-induced cardiac dysfunction and remodeling in fibroblast growth factor 21 (FGF21)-dependent manner.
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Garcia-Ramírez M, Hernández C, Palomer X, Vázquez-Carrera M, Simó R. Fenofibrate prevents the disruption of the outer blood retinal barrier through downregulation of NF-κB activity. Acta Diabetol 2016; 53:109-18. [PMID: 25936740 DOI: 10.1007/s00592-015-0759-3] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/29/2014] [Accepted: 04/12/2015] [Indexed: 10/23/2022]
Abstract
AIMS There is clinical evidence that fenofibrate, a PPARα agonist, arrests the progression of diabetic macular edema (DME). However, the underlying mechanisms of this beneficial effect remain to be elucidated. We previously reported that fenofibric acid (FA), the active metabolite of fenofibrate, prevents the disorganization of tight junction proteins and the hyperpermeability provoked by the diabetic milieu in the retinal pigment epithelium (RPE). The aim of the present study was to evaluate whether this effect is mediated by inhibiting the proinflammatory transcription factor NF-κB, as well as the expression of several proinflammatory cytokines involved in the pathogenesis of DME. METHODS Human RPE cells were cultured under standard conditions and under conditions leading to the disruption of the monolayer [IL-1β (10 ng/ml)]. The effect of FA, QNZ (a NF-κB inhibitor), WY14643 (a PPARα agonist), and MK-866 (a PPARα antagonist) in the disruption of the monolayer was determined by dextran permeability and immunohistochemistry analyses. The effect of FA on NF-κB activity was assessed by EMSA and by NF-κB/p65 nuclear translocation analyses. The expression of cytokines (IL-6, IL-8, MCP-1) was measured by RT-PCR. RESULTS FA prevented RPE monolayer disruption, and the consequent hyperpermeability induced by IL-1β, through inhibition of NF-κB activity. This effect was due to PPARα activation and was associated with a significant downregulation of the expression of proinflammatory cytokines. CONCLUSIONS Our findings suggest that the anti-inflammatory effects of FA through inhibition of NF-κB activity play a key role in the beneficial effect of fenofibrate for treating DME.
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Affiliation(s)
- Marta Garcia-Ramírez
- Diabetes and Metabolism Research Unit, Vall d'Hebron Research Institute, Universitat Autònoma de Barcelona, Pg. Vall d'Hebron 119-129, 08035, Barcelona, Spain
- Centro de Investigación Biomédica en Red de Diabetes y Enfermedades Metabólicas Asociadas (CIBERDEM), Instituto de Salud Carlos III (ISCIII), Madrid, Spain
| | - Cristina Hernández
- Diabetes and Metabolism Research Unit, Vall d'Hebron Research Institute, Universitat Autònoma de Barcelona, Pg. Vall d'Hebron 119-129, 08035, Barcelona, Spain
- Centro de Investigación Biomédica en Red de Diabetes y Enfermedades Metabólicas Asociadas (CIBERDEM), Instituto de Salud Carlos III (ISCIII), Madrid, Spain
| | - Xavier Palomer
- Centro de Investigación Biomédica en Red de Diabetes y Enfermedades Metabólicas Asociadas (CIBERDEM), Instituto de Salud Carlos III (ISCIII), Madrid, Spain
- Department of Pharmacology and Therapeutic Chemistry and Institute of Biomedicine of the University of Barcelona (IBUB), Faculty of Pharmacy, University of Barcelona, Barcelona, Spain
| | - Manuel Vázquez-Carrera
- Centro de Investigación Biomédica en Red de Diabetes y Enfermedades Metabólicas Asociadas (CIBERDEM), Instituto de Salud Carlos III (ISCIII), Madrid, Spain
- Department of Pharmacology and Therapeutic Chemistry and Institute of Biomedicine of the University of Barcelona (IBUB), Faculty of Pharmacy, University of Barcelona, Barcelona, Spain
| | - Rafael Simó
- Diabetes and Metabolism Research Unit, Vall d'Hebron Research Institute, Universitat Autònoma de Barcelona, Pg. Vall d'Hebron 119-129, 08035, Barcelona, Spain.
- Centro de Investigación Biomédica en Red de Diabetes y Enfermedades Metabólicas Asociadas (CIBERDEM), Instituto de Salud Carlos III (ISCIII), Madrid, Spain.
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Park JS, Kang DH, Lee DH, Bae SH. Fenofibrate activates Nrf2 through p62-dependent Keap1 degradation. Biochem Biophys Res Commun 2015; 465:542-7. [DOI: 10.1016/j.bbrc.2015.08.056] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2015] [Accepted: 08/12/2015] [Indexed: 12/27/2022]
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Abstract
Type 2 diabetes is a pandemic disease, and its prevalence is increasing mainly due to an increase in obesity and life expectancy. Diabetic complications and their comorbidities constitute the most important economic cost of the disease and represent a significant economic burden for the healthcare systems of developed countries. Despite improving standards of care, people with diabetes remain at risk of the development and progression of microvascular diabetic complications. Therefore, the identification of novel therapeutic approaches is necessary. The aim of this article is to provide an overview of the clinical benefits of fenofibrate on microvascular diabetic complications, with special emphasis on diabetic retinopathy. In addition, the potential mechanisms of action will be briefly discussed.
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Affiliation(s)
- Rafael Simó
- Diabetes and Metabolism Research Unit. Vall d'Hebron Research Institute (VHIR), Universitat Autònoma de Barcelona, Passeig Vall d'Hebron 119-129, 08035, Barcelona, Spain,
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Jinmaitong (筋脉通) alleviates the diabetic peripheral neuropathy by inducing autophagy. Chin J Integr Med 2015; 22:185-92. [DOI: 10.1007/s11655-015-2164-8] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2013] [Indexed: 12/27/2022]
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Gong X, Rubin LP. Role of macular xanthophylls in prevention of common neovascular retinopathies: retinopathy of prematurity and diabetic retinopathy. Arch Biochem Biophys 2015; 572:40-48. [PMID: 25701588 DOI: 10.1016/j.abb.2015.02.004] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2014] [Revised: 02/03/2015] [Accepted: 02/08/2015] [Indexed: 12/20/2022]
Abstract
Retinopathy of prematurity (ROP) and diabetic retinopathy (DR) are important causes of blindness among children and working-age adults, respectively. The development of both diseases involves retinal microvascular degeneration, vessel loss and consequent hypoxic and inflammatory pathologic retinal neovascularization. Mechanistic studies have shown that oxidative stress and subsequent derangement of cell signaling are important factors in disease progression. In eye and vision research, role of the dietary xanthophyll carotenoids, lutein and zeaxanthin, has been more extensively studied in adult onset macular degeneration than these other retinopathies. These carotenoids also may decrease severity of ROP in preterm infants and of DR in working-age adults. A randomized controlled clinical trial of carotenoid supplementation in preterm infants indicated that lutein has functional effects in the neonatal eye and is anti-inflammatory. Three multicenter clinical trials all showed a trend of decreased ROP severity in the lutein supplemented group. Prospective studies on patients with non-proliferative DR indicate serum levels of lutein and zeaxanthin are significantly lower in these patients compared to normal subjects. The present review describes recent advances in lutein and zeaxanthin modulation of oxidative stress and inflammation related to ROP and DR and discusses potential roles of lutein/zeaxanthin in preventing or lessening the risks of disease initiation or progression.
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Affiliation(s)
- Xiaoming Gong
- Department of Pediatrics, Texas Tech University Health Science Center, Paul L. Foster School of Medicine, El Paso, TX 79905, USA
| | - Lewis P Rubin
- Department of Pediatrics, Texas Tech University Health Science Center, Paul L. Foster School of Medicine, El Paso, TX 79905, USA.
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Lu Y, Cheng J, Chen L, Li C, Chen G, Gui L, Shen B, Zhang Q. Endoplasmic reticulum stress involved in high-fat diet and palmitic acid-induced vascular damages and fenofibrate intervention. Biochem Biophys Res Commun 2015; 458:1-7. [DOI: 10.1016/j.bbrc.2014.12.123] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2014] [Accepted: 12/18/2014] [Indexed: 12/25/2022]
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Bogdanov P, Hernández C, Corraliza L, Carvalho AR, Simó R. Effect of fenofibrate on retinal neurodegeneration in an experimental model of type 2 diabetes. Acta Diabetol 2015; 52:113-22. [PMID: 25029994 DOI: 10.1007/s00592-014-0610-2] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/28/2014] [Accepted: 05/29/2014] [Indexed: 12/28/2022]
Abstract
There is now consistent evidence from two major clinical trials (the Fenofibrate Intervention and Event Lowering in Diabetes and the Action to Control Cardiovascular Risk in Diabetes Eye) that fenofibrate arrests the progression of diabetic retinopathy in type 2 diabetic patients. However, the underlying mechanisms of this beneficial effect remain to be elucidated. The aim of the study was to evaluate the potential effect of fenofibric acid (FA), the active metabolite of fenofibrate, in preventing retinal neurodegeneration in an experimental mouse model of type 2 diabetes. For this purpose, we evaluated a total of 24 diabetic mice (db/db) aged 8 weeks that were randomly assigned to daily oral treatment (by gavage) with FA (100 mg/kg/day) (n = 12) or vehicle (n = 12) for 1 week. Ten non-diabetic mice (db/+) were used as control group. Retinal neurodegeneration was evaluated by measuring glial activation (immunofluorescence and Western blot) and apoptosis. Glutamate/aspartate transporter (GLAST) was assessed by immunofluorescence. Functional abnormalities were assessed by electroretinography (ERG). We observed that diabetic mice presented significantly higher glial activation and apoptosis in ganglion cell layer (GCL) than in age-matched non-diabetic mice. Treatment with FA resulted in a significant decrease in both glial activation and the rate of apoptosis in GCL in comparison with diabetic mice treated with vehicle. In addition, FA prevented GLAST downregulation induced by diabetes. Furthermore, a significant improvement of ERG parameters (oscillatory potential amplitudes and b-wave implicit time) was observed. We conclude that FA prevents retinal neurodegeneration induced by diabetes. Our results suggest that neuroprotection is one of the underlying mechanisms by which fenofibrate exerts its beneficial actions in diabetic retinopathy.
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Affiliation(s)
- Patricia Bogdanov
- Diabetes and Metabolism Research Unit, Vall d'Hebron Research Institute, Universitat Autònoma de Barcelona, Pg. Vall d'Hebron 119-129, 08035, Barcelona, Spain
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Simó R, Ballarini S, Cunha-Vaz J, Ji L, Haller H, Zimmet P, Wong TY. Non-traditional systemic treatments for diabetic retinopathy: an evidence-based review. Curr Med Chem 2015; 22:2580-9. [PMID: 25989912 PMCID: PMC4997935 DOI: 10.2174/0929867322666150520095923] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2015] [Revised: 05/05/2015] [Accepted: 05/18/2015] [Indexed: 01/07/2023]
Abstract
The rapid escalation in the global prevalence diabetes, with more than 30% being afflicted with diabetic retinopathy (DR), means it is likely that associated vision-threatening conditions will also rise substantially. This means that new therapeutic approaches need to be found that go beyond the current standards of diabetic care, and which are effective in the early stages of the disease. In recent decades several new pharmacological agents have been investigated for their effectiveness in preventing the appearance and progression of DR or in reversing DR; some with limited success while others appear promising. This up-to-date critical review of non-traditional systemic treatments for DR is based on the published evidence in MEDLINE spanning 1980-December 2014. It discusses a number of therapeutic options, paying particular attention to the mechanisms of action and the clinical evidence for the use of renin-angiotensin system blockade, fenofibrate and calcium dobesilate monohydrate in DR.
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Affiliation(s)
- Rafael Simó
- Diabetes and Metabolism Reseach Unit. Vall d'Hebron Research Institute. Universitat Autonoma de Barcelona and Centro de Investigacion Biomedica en Red de Diabetes y Enfermedades Metabolicas Asociadas (CIBERDEM), Instituto de Salud Carlos III (ISCIII). Barcelona, Spain Pg. Vall d'Hebron 119-129. 08035 Barcelona, Spain.
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Wang H, Liao S, Geng R, Zheng Y, Liao R, Yan F, Thrimawithana T, Little PJ, Feng ZP, Lazarovici P, Zheng W. IGF-1 signaling via the PI3K/Akt pathway confers neuroprotection in human retinal pigment epithelial cells exposed to sodium nitroprusside insult. J Mol Neurosci 2014; 55:931-40. [PMID: 25339505 DOI: 10.1007/s12031-014-0448-7] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2014] [Accepted: 10/13/2014] [Indexed: 02/01/2023]
Abstract
The pathological increase in the levels of the second messenger nitric oxide (NO) in the vitreous cavity and retina leads to injury and cell death of the retinal pigment epithelium (RPE) cells and eventually may contribute to the occurrence and development of diabetic retinopathy. In this study, we developed a cellular model of retinopathy using D407 cells (a human RPE cell line) exposed to sodium nitroprusside (SNP) and investigated the protective effect of the insulin-like growth factor-1 (IGF-1) towards this insult. Cell death and apoptosis were examined by the methyl thiazolyl tetrazolium assay and Hoechst staining, respectively. Specific inhibitors were used and phosphorylation of relevant signaling proteins was determined by Western blotting. SNP, in a concentration-dependent fashion, increased the production of reactive oxygen species (ROS) and lipid peroxidation process causing cell death by apoptosis of D407 cells. IGF-1, in a time- and dose-dependent manner, conferred protection towards SNP-mediated insult. Both phosphatidylinositol-3-kinase/protein kinase B (PI3K/Akt) and mitogen-activated protein kinase (MAPK) were activated by IGF-1 in relation to the protective effect. Blockade of the PI3K/Akt pathway abolished the protective effect of IGF-1 whereas inhibition of the MAPK pathway was ineffective. SNP decreased the phosphorylation of Akt in the cells while IGF-1 reversed this inhibitory effect. These results indicate that the protective effect of IGF-1 on D407 exposed to SNP insult is mediated by the PI3K/Akt pathway. This proposal may be exploited in the clinic to improve the viability of insulted retinal cells for maintaining physiological vision.
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Affiliation(s)
- Haitao Wang
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou, 510060, China
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48
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Arredondo Zamarripa D, Díaz-Lezama N, Meléndez García R, Chávez Balderas J, Adán N, Ledesma-Colunga MG, Arnold E, Clapp C, Thebault S. Vasoinhibins regulate the inner and outer blood-retinal barrier and limit retinal oxidative stress. Front Cell Neurosci 2014; 8:333. [PMID: 25368550 PMCID: PMC4202700 DOI: 10.3389/fncel.2014.00333] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2014] [Accepted: 09/30/2014] [Indexed: 12/11/2022] Open
Abstract
Vasoinhibins are prolactin fragments present in the retina, where they have been shown to prevent the hypervasopermeability associated with diabetes. Enhanced bradykinin (BK) production contributes to the increased transport through the blood-retina barrier (BRB) in diabetes. Here, we studied if vasoinhibins regulate BRB permeability by targeting the vascular endothelium and retinal pigment epithelium (RPE) components of this barrier. Intravitreal injection of BK in male rats increased BRB permeability. Vasoinhibins prevented this effect, as did the B2 receptor antagonist Hoe-140. BK induced a transient decrease in mouse retinal and brain capillary endothelial monolayer resistance that was blocked by vasoinhibins. Both vasoinhibins and the nitric oxide (NO) synthase inhibitor L-NAME, but not the antioxidant N-acetyl cysteine (NAC), blocked the transient decrease in bovine umbilical vein endothelial cell (BUVEC) monolayer resistance induced by BK; this block was reversed by the NO donor DETANONOate. Vasoinhibins also prevented the BK-induced actin cytoskeleton redistribution, as did L-NAME. BK transiently decreased human RPE (ARPE-19) cell monolayer resistance, and this effect was blocked by vasoinhibins, L-NAME, and NAC. DETANONOate reverted the blocking effect of vasoinhibins. Similar to BK, the radical initiator Luperox induced a reduction in ARPE-19 cell monolayer resistance, which was prevented by vasoinhibins. These effects on RPE resistance coincided with actin cytoskeleton redistribution. Intravitreal injection of vasoinhibins reduced the levels of reactive oxygen species (ROS) in retinas of streptozotocin-induced diabetic rats, particularly in the RPE and capillary-containing layers. Thus, vasoinhibins reduce BRB permeability by targeting both its main inner and outer components through NO- and ROS-dependent pathways, offering potential treatment strategies against diabetic retinopathies.
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Affiliation(s)
- David Arredondo Zamarripa
- Departamento de Neurobiología Celular y Molecular, Instituto de Neurobiología, Universidad Nacional Autónoma de México Querétaro, México
| | - Nundehui Díaz-Lezama
- Departamento de Neurobiología Celular y Molecular, Instituto de Neurobiología, Universidad Nacional Autónoma de México Querétaro, México
| | - Rodrigo Meléndez García
- Departamento de Neurobiología Celular y Molecular, Instituto de Neurobiología, Universidad Nacional Autónoma de México Querétaro, México
| | - Jesús Chávez Balderas
- Departamento de Neurobiología Celular y Molecular, Instituto de Neurobiología, Universidad Nacional Autónoma de México Querétaro, México
| | - Norma Adán
- Departamento de Neurobiología Celular y Molecular, Instituto de Neurobiología, Universidad Nacional Autónoma de México Querétaro, México
| | - Maria G Ledesma-Colunga
- Departamento de Neurobiología Celular y Molecular, Instituto de Neurobiología, Universidad Nacional Autónoma de México Querétaro, México
| | - Edith Arnold
- Departamento de Neurobiología Celular y Molecular, Instituto de Neurobiología, Universidad Nacional Autónoma de México Querétaro, México
| | - Carmen Clapp
- Departamento de Neurobiología Celular y Molecular, Instituto de Neurobiología, Universidad Nacional Autónoma de México Querétaro, México
| | - Stéphanie Thebault
- Departamento de Neurobiología Celular y Molecular, Instituto de Neurobiología, Universidad Nacional Autónoma de México Querétaro, México
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49
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Kim DI, Park MJ, Lim SK, Choi JH, Kim JC, Han HJ, Kundu TK, Park JI, Yoon KC, Park SW, Park JS, Heo YR, Park SH. High-glucose-induced CARM1 expression regulates apoptosis of human retinal pigment epithelial cells via histone 3 arginine 17 dimethylation: Role in diabetic retinopathy. Arch Biochem Biophys 2014; 560:36-43. [DOI: 10.1016/j.abb.2014.07.021] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2014] [Revised: 07/14/2014] [Accepted: 07/17/2014] [Indexed: 01/21/2023]
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50
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Qu L, Liang X, Gu B, Liu W. Quercetin alleviates high glucose-induced Schwann cell damage by autophagy. Neural Regen Res 2014; 9:1195-203. [PMID: 25206782 PMCID: PMC4146282 DOI: 10.4103/1673-5374.135328] [Citation(s) in RCA: 53] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 05/16/2014] [Indexed: 01/02/2023] Open
Abstract
Quercetin can reverse high glucose-induced inhibition of neural cell proliferation, and therefore may have a neuroprotective effect in diabetic peripheral neuropathy. It is difficult to obtain primary Schwann cells and RSC96 cells could replace primary Schwann cells in studies of the role of autophagy in the mechanism underlying diabetic peripheral neuropathy. Here, we show that under high glucose conditions, there are fewer autophagosomes in immortalized rat RSC96 cells and primary rat Schwann cells than under control conditions, the proliferative activity of both cell types is significantly impaired, and the expression of Beclin-1 and LC3, the molecular markers for autophagy, is significantly lower. After intervention with quercetin, the autophagic and proliferative activity of both cell types is rescued. These results suggest that quercetin can alleviate high glucose-induced damage to Schwann cells by autophagy.
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Affiliation(s)
- Ling Qu
- Department of Traditional Chinese Medicine, Peking Union Medical College Hospital, Peking Union Medical College, China Academy of Medical Sciences, Beijing, China
| | - Xiaochun Liang
- Department of Traditional Chinese Medicine, Peking Union Medical College Hospital, Peking Union Medical College, China Academy of Medical Sciences, Beijing, China
| | - Bei Gu
- Cell Center, Institute of Basic Medical Science, Peking Union Medical College, China Academy of Medical Sciences, Beijing, China
| | - Wei Liu
- Department of Traditional Chinese Medicine, Peking Union Medical College Hospital, Peking Union Medical College, China Academy of Medical Sciences, Beijing, China
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