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Li J, Chen K, Li X, Zhang X, Zhang L, Yang Q, Xia Y, Xie C, Wang X, Tong J, Shen Y. Mechanistic insights into the alterations and regulation of the AKT signaling pathway in diabetic retinopathy. Cell Death Discov 2023; 9:418. [PMID: 37978169 PMCID: PMC10656479 DOI: 10.1038/s41420-023-01717-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2023] [Revised: 11/05/2023] [Accepted: 11/08/2023] [Indexed: 11/19/2023] Open
Abstract
In the early stages of diabetic retinopathy (DR), diabetes-related hyperglycemia directly inhibits the AKT signaling pathway by increasing oxidative stress or inhibiting growth factor expression, which leads to retinal cell apoptosis, nerve proliferation and fundus microvascular disease. However, due to compensatory vascular hyperplasia in the late stage of DR, the vascular endothelial growth factor (VEGF)/phosphatidylinositol 3 kinase (PI3K)/AKT cascade is activated, resulting in opposite levels of AKT regulation compared with the early stage. Studies have shown that many factors, including insulin, insulin-like growth factor-1 (IGF-1), VEGF and others, can regulate the AKT pathway. Disruption of the insulin pathway decreases AKT activation. IGF-1 downregulation decreases the activation of AKT in DR, which abrogates the neuroprotective effect, upregulates VEGF expression and thus induces neovascularization. Although inhibiting VEGF is the main treatment for neovascularization in DR, excessive inhibition may lead to apoptosis in inner retinal neurons. AKT pathway substrates, including mammalian target of rapamycin (mTOR), forkhead box O (FOXO), glycogen synthase kinase-3 (GSK-3)/nuclear factor erythroid 2-related factor 2 (Nrf2), and nuclear factor kappa-B (NF-κB), are a research focus. mTOR inhibitors can delay or prevent retinal microangiopathy, whereas low mTOR activity can decrease retinal protein synthesis. Inactivated AKT fails to inhibit FOXO and thus causes apoptosis. The GSK-3/Nrf2 cascade regulates oxidation and inflammation in DR. NF-κB is activated in diabetic retinas and is involved in inflammation and apoptosis. Many pathways or vital activities, such as the Janus kinase (JAK)/signal transducer and activator of transcription (STAT) and mitogen-activated protein kinase (MAPK) signaling pathways, interact with the AKT pathway to influence DR development. Numerous regulatory methods can simultaneously impact the AKT pathway and other pathways, and it is essential to consider both the connections and interactions between these pathways. In this review, we summarize changes in the AKT signaling pathway in DR and targeted drugs based on these potential sites.
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Affiliation(s)
- Jiayuan Li
- Department of Ophthalmology, The First Affiliated Hospital of Zhejiang University, Hangzhou, Zhejiang, China
- Department of Cardiology, The Second Affiliated Hospital of Zhejiang University, Hangzhou, Zhejiang, China
| | - Kuangqi Chen
- Department of Ophthalmology, The First Affiliated Hospital of Zhejiang University, Hangzhou, Zhejiang, China
| | - Xiang Li
- Department of Ophthalmology, The First Affiliated Hospital of Zhejiang University, Hangzhou, Zhejiang, China
| | - Xuhong Zhang
- Department of Ophthalmology, The First Affiliated Hospital of Zhejiang University, Hangzhou, Zhejiang, China
| | - Liyue Zhang
- Department of Ophthalmology, The First Affiliated Hospital of Zhejiang University, Hangzhou, Zhejiang, China
| | - Qianjie Yang
- Department of Ophthalmology, The First Affiliated Hospital of Zhejiang University, Hangzhou, Zhejiang, China
| | - Yutong Xia
- Department of Ophthalmology, The First Affiliated Hospital of Zhejiang University, Hangzhou, Zhejiang, China
| | - Chen Xie
- Department of Ophthalmology, The First Affiliated Hospital of Zhejiang University, Hangzhou, Zhejiang, China
| | - Xiawei Wang
- Department of Ophthalmology, The First Affiliated Hospital of Zhejiang University, Hangzhou, Zhejiang, China
| | - Jianping Tong
- Department of Ophthalmology, The First Affiliated Hospital of Zhejiang University, Hangzhou, Zhejiang, China.
| | - Ye Shen
- Department of Ophthalmology, The First Affiliated Hospital of Zhejiang University, Hangzhou, Zhejiang, China.
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Anti-CXCL10 monoclonal antibody therapy protects against the diabetic retinopathy in the mouse model induced by streptozotocin. Tissue Cell 2022; 76:101745. [DOI: 10.1016/j.tice.2022.101745] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2021] [Revised: 01/03/2022] [Accepted: 01/25/2022] [Indexed: 11/19/2022]
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Liu G, Wu F, Wu H, Wang Y, Jiang X, Hu P, Tong X. Inactivation of cysteine 674 in the sarcoplasmic/endoplasmic reticulum calcium ATPase 2 causes retinopathy in the mouse. Exp Eye Res 2021; 207:108559. [PMID: 33848522 DOI: 10.1016/j.exer.2021.108559] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2020] [Revised: 03/01/2021] [Accepted: 03/23/2021] [Indexed: 12/12/2022]
Abstract
Diabetic retinopathy is a multifactorial microvascular complication, and its pathogenesis hasn't been fully elucidated. The irreversible oxidation of cysteine 674 (C674) in the sarcoplasmic/endoplasmic reticulum calcium ATPase 2 (SERCA2) was increased in the type 1 diabetic retinal vasculature. SERCA2 C674S knock-in (SKI) mouse line that half of C674 was replaced by serine 674 (S674) was used to study the effect of C674 inactivation on retinopathy. Compared with wild type (WT) mice, SKI mice had increased number of acellular capillaries and pericyte loss similar to those in type 1 diabetic WT mice. In the retina of SKI mice, pro-apoptotic proteins and intracellular Ca2+-dependent signaling pathways increased, while anti-apoptotic proteins and vessel density decreased. In endothelial cells, C674 inactivation increased the expression of pro-apoptotic proteins, damaged mitochondria, and induced cell apoptosis. These results suggest that a possible mechanism of retinopathy induced by type 1 diabetes is the interruption of calcium homeostasis in the retina by oxidation of C674. C674 is a key to maintain retinal health. Its inactivation can cause retinopathy similar to type 1 diabetes by promoting apoptosis. SERCA2 might be a potential target for the prevention and treatment of diabetic retinopathy.
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Affiliation(s)
- Gang Liu
- Chongqing Key Laboratory of Natural Product Synthesis and Drug Research, School of Pharmaceutical Sciences, Chongqing University, Chongqing, 401331, China; Henan Key Laboratory of Medical Tissue Regeneration, College of Basic Medical Sciences, Xinxiang Medical University, Xinxiang, Henan, 453003, China
| | - Fuhua Wu
- Chongqing Key Laboratory of Natural Product Synthesis and Drug Research, School of Pharmaceutical Sciences, Chongqing University, Chongqing, 401331, China
| | - Haixia Wu
- Chongqing Key Laboratory of Natural Product Synthesis and Drug Research, School of Pharmaceutical Sciences, Chongqing University, Chongqing, 401331, China
| | - Yaping Wang
- Chongqing Key Laboratory of Natural Product Synthesis and Drug Research, School of Pharmaceutical Sciences, Chongqing University, Chongqing, 401331, China
| | - Xiaoli Jiang
- Chongqing Key Laboratory of Natural Product Synthesis and Drug Research, School of Pharmaceutical Sciences, Chongqing University, Chongqing, 401331, China
| | - Pingping Hu
- Chongqing Key Laboratory of Natural Product Synthesis and Drug Research, School of Pharmaceutical Sciences, Chongqing University, Chongqing, 401331, China.
| | - Xiaoyong Tong
- Chongqing Key Laboratory of Natural Product Synthesis and Drug Research, School of Pharmaceutical Sciences, Chongqing University, Chongqing, 401331, China.
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Jiang H, Zhang H, Jiang X, Wu S. Overexpression of D-amino acid oxidase prevents retinal neurovascular pathologies in diabetic rats. Diabetologia 2021; 64:693-706. [PMID: 33319325 DOI: 10.1007/s00125-020-05333-y] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/25/2020] [Accepted: 10/06/2020] [Indexed: 10/22/2022]
Abstract
AIMS/HYPOTHESIS Diabetic retinopathy is characterised by retinal neurodegeneration and retinal vascular abnormalities, affecting one third of diabetic patients with disease duration of more than 10 years. Accumulated evidence suggests that serine racemase (SR) and D-serine are correlated with the pathogenesis of diabetic retinopathy and the deletion of the Srr gene reverses neurovascular pathologies in diabetic mice. Since D-serine content is balanced by SR synthesis and D-amino acid oxidase (DAAO) degradation, we examined the roles of DAAO in diabetic retinopathy and further explored relevant therapy. METHODS Rats were used as a model of diabetes by i.p. injection of streptozotocin at the age of 2 months and blood glucose was monitored with a glucometer. Quantitative real-time PCR was used to examine Dao mRNA and western blotting to examine targeted proteins in the retinas. Bisulphite sequencing was used to examine the methylation of Dao mRNA promoter in the retinas. Intravitreal injection of DAAO-expressing adenovirus (AAV8-DAAO) was conducted one week before streptozotocin administration. Brain specific homeobox/POU domain protein 3a (Brn3a) immunofluorescence was conducted to indicate retinal ganglion cells at 3 months after virus injection. The permeability of the blood-retinal barrier was examined by Evans blue leakage from retinal capillaries. Periodic acid-Schiff staining and haematoxylin counterstaining were used to indicate retinal vasculature, which was further examined with double immunostaining at 7 months after virus injection. RESULTS At the age of 12 months, DAAO mRNA and protein levels in retinas from diabetic animals were reduced to 66.2% and 70.4% of those from normal (control) animals, respectively. The Dao proximal promoter contained higher levels of methylation in diabetic than in normal retinas. Consistent with the observation, DNA methyltransferase 1 was increased in diabetic retinas. Injection of DAAO-expressing virus completely prevented the loss of retinal ganglion cells and the disruption of blood-retinal barrier in diabetic rats. Diabetic retinas contained retinal ganglion cells at a density of 54 ± 4/mm2, which was restored to 68 ± 9/mm2 by DAAO overexpression, similar to the levels in normal retinas. The ratio between the number of endothelial cells and pericytes in diabetic retinas was 6.06 ± 1.93/mm2, which was reduced to 3.42 ± 0.55/mm2 by DAAO overexpression; the number of acellular capillaries in diabetic retinas was 10 ± 5/mm2, which was restored to 6 ± 2/mm2 by DAAO overexpression, similar to the levels in normal retinas. Injection of the DAAO-expressing virus increased the expression of occludin and reduced gliosis, which were examined to probe the mechanism by which the disrupted blood-retinal barrier in diabetic rats was rescued and retinal neurodegeneration was prevented. CONCLUSIONS/INTERPRETATION Altogether, overexpression of DAAO before the onset of diabetes protects against neurovascular abnormalities in retinas from diabetic rats, which suggests a novel strategy for preventing diabetic retinopathy. Graphical abstract.
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Affiliation(s)
- Haiyan Jiang
- School of Optometry and Ophthalmology and the Eye Hospital, Wenzhou Medical University, Wenzhou, Zhejiang, People's Republic of China
- State Key Laboratory of Optometry, Ophthalmology, and Visual Science, Wenzhou, Zhejiang, People's Republic of China
| | - He Zhang
- School of Optometry and Ophthalmology and the Eye Hospital, Wenzhou Medical University, Wenzhou, Zhejiang, People's Republic of China
- State Key Laboratory of Optometry, Ophthalmology, and Visual Science, Wenzhou, Zhejiang, People's Republic of China
- College of Life and Environmental Sciences, Wenzhou University, Wenzhou, Zhejiang, People's Republic of China
| | - Xue Jiang
- School of Optometry and Ophthalmology and the Eye Hospital, Wenzhou Medical University, Wenzhou, Zhejiang, People's Republic of China
- State Key Laboratory of Optometry, Ophthalmology, and Visual Science, Wenzhou, Zhejiang, People's Republic of China
| | - Shengzhou Wu
- School of Optometry and Ophthalmology and the Eye Hospital, Wenzhou Medical University, Wenzhou, Zhejiang, People's Republic of China.
- State Key Laboratory of Optometry, Ophthalmology, and Visual Science, Wenzhou, Zhejiang, People's Republic of China.
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Wang Z, Ding L, Zhu J, Su Y, Wang L, Liu L, Ma Q, Yao H. Long non-coding RNA MEG3 mediates high glucose-induced endothelial cell dysfunction. INTERNATIONAL JOURNAL OF CLINICAL AND EXPERIMENTAL PATHOLOGY 2018; 11:1088-1100. [PMID: 31938204 PMCID: PMC6958101] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Received: 11/30/2017] [Accepted: 12/22/2017] [Indexed: 06/10/2023]
Abstract
Long noncoding RNAs (lncRNAs) are implicated in the progression of diabetes mellitus (DM) and diabetes-induced endothelial dysfunction. Maternally expressed gene 3 (MEG3) encodes an lncRNA which is suggested to function as a tumor suppressor. Therefore, the aim of the present study was to investigate whether MEG3 is a potential regulator and molecular biomarker of high glucose-induced endothelial dysfunction. LncRNA Meg3-specific small interfering RNA (siRNA) and scrambled (Scr) siRNA were transfected for MEG3 dysfunction studies. RNA and protein expression were examined by quantitative RT-PCR (qPCR) and Western blot, respectively. The percentage of apoptotic cells was measured by flow cytometry. Cell viability was determined through MTT assay. This study demonstrates involvement of lncRNA MEG3 in high glucose-induced endothelial dysfunction. MEG3 is significantly downregulated in an endothelial cell model of hyperglycemia. In addition, MEG3 knockdown could exacerbate inflammatory damage in endothelial cells. Interestingly, MEG3 knockdown in HUVECs significantly induced proliferation and inhibited apoptosis by upregulating Bcl-2 and downregulating Bax, caspase-3, and P53. It should be noted that MEG3 knockdown could activate the TGF-β signaling pathway via upregulating TGF-β1, SMAD2, and SMAD7 and activate the Wnt/β-catenin signaling pathway via upregulating β-catenin and Cyclin D1 and downregulating TCF7L2. Our results indicate that MEG3 can be regarded as a novel therapeutic target and molecular biomarker for high glucose-induced endothelial dysfunction.
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Affiliation(s)
- Zhiqiang Wang
- Department of Public Health, Xinjiang Medical UniversityUrumqi, Xinjiang, China
- Xinjiang Key Laboratory of Metabolic Disease Research, The First Affiliated Hospital of Xinjiang Medical UniversityUrumqi, Xinjiang, China
| | - Lili Ding
- Department of Public Health, Xinjiang Medical UniversityUrumqi, Xinjiang, China
- Department of Infection Control, The First Affiliated Hospital of Xinjiang Medical UniversityUrumqi, Xinjiang, China
| | - Jun Zhu
- Xinjiang Key Laboratory of Metabolic Disease Research, The First Affiliated Hospital of Xinjiang Medical UniversityUrumqi, Xinjiang, China
- Department of Endocrinology, The First Affiliated Hospital of Xinjiang Medical UniversityUrumqi, Xinjiang, China
| | - Yinxia Su
- Xinjiang Key Laboratory of Metabolic Disease Research, The First Affiliated Hospital of Xinjiang Medical UniversityUrumqi, Xinjiang, China
| | - Li Wang
- Xinjiang Key Laboratory of Metabolic Disease Research, The First Affiliated Hospital of Xinjiang Medical UniversityUrumqi, Xinjiang, China
| | - Lina Liu
- Department of Endocrinology, Branch of The First Affiliated Hospital of Xinjiang Medical UniversityChangji, Xinjiang, China
| | - Qi Ma
- Xinjiang Key Laboratory of Metabolic Disease Research, The First Affiliated Hospital of Xinjiang Medical UniversityUrumqi, Xinjiang, China
| | - Hua Yao
- Xinjiang Key Laboratory of Metabolic Disease Research, The First Affiliated Hospital of Xinjiang Medical UniversityUrumqi, Xinjiang, China
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Francis AW, Wanek J, Shahidi M. Assessment of Global and Local Alterations in Retinal Layer Thickness in Ins2 (Akita) Diabetic Mice by Spectral Domain Optical Coherence Tomography. J Ophthalmol 2018; 2018:7253498. [PMID: 29675273 PMCID: PMC5838457 DOI: 10.1155/2018/7253498] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2017] [Accepted: 12/24/2017] [Indexed: 12/27/2022] Open
Abstract
PURPOSE/AIM The Ins2 (Akita) mouse is a spontaneous diabetic mouse model with a heterozygous mutation in the insulin 2 gene that results in sustained hyperglycemia. The purpose of the study was to assess global and local retinal layer thickness alterations in Akita mice by analysis of spectral domain optical coherence tomography (SD-OCT) images. MATERIALS AND METHODS SD-OCT imaging was performed in Akita and wild-type mice at 12 and 24 weeks of age. Inner retinal thickness (IRT), outer retinal thickness (ORT), total retinal thickness (TRT), and photoreceptor outer segment length (OSL) were measured. Mean global thickness values were compared between Akita and wild-type mice. Local thickness variations in Akita mice were assessed based on normative values in wild-type mice. RESULTS Akita mice had higher blood glucose levels and lower body weights (p < 0.001). On average, IRT, ORT, and TRT were approximately 2% lower in Akita mice than in wild-type mice (p ≤ 0.02). In Akita mice, the percent difference between retinal areas with thickness below and above normative values for IRT, ORT, and TRT was 22%, 32%, and 38%, respectively. CONCLUSIONS These findings support the use of the Akita mouse model to study the retinal neurodegenerative effects of hyperglycemia.
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Affiliation(s)
- Andrew W. Francis
- Department of Ophthalmology, University of California San Francisco, San Francisco, CA, USA
| | - Justin Wanek
- Department of Ophthalmology and Visual Sciences, University of Illinois at Chicago, Chicago, IL, USA
| | - Mahnaz Shahidi
- Department of Ophthalmology, University of Southern California, Los Angeles, CA, USA
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Aldose reductase, ocular diabetic complications and the development of topical Kinostat®. Prog Retin Eye Res 2016; 54:1-29. [DOI: 10.1016/j.preteyeres.2016.04.006] [Citation(s) in RCA: 44] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2016] [Revised: 04/11/2016] [Accepted: 04/14/2016] [Indexed: 12/20/2022]
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Angbohang A, Wu N, Charalambous T, Eastlake K, Lei Y, Kim YS, Sun XH, Limb GA. Downregulation of the Canonical WNT Signaling Pathway by TGFβ1 Inhibits Photoreceptor Differentiation of Adult Human Müller Glia with Stem Cell Characteristics. Stem Cells Dev 2016; 25:1-12. [PMID: 26456050 PMCID: PMC4692127 DOI: 10.1089/scd.2015.0262] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2015] [Accepted: 10/09/2015] [Indexed: 12/29/2022] Open
Abstract
Müller glia are responsible for the retina regeneration observed in zebrafish. Although the human retina harbors Müller glia with stem cell characteristics, there is no evidence that they regenerate the retina after disease or injury. Transforming growth factor-β (TGFβ) and Wnt signaling regulate retinal neurogenesis and inflammation, but their roles in the neural differentiation of human Müller stem cells (hMSC) are not known. We examined hMSC lines in vitro for the expression of various Wnt signaling components and for their modulation by TGFβ1, as well as the effect of this cytokine on the photoreceptor differentiation of these cells. Culture of hMSC with a combination of factors that induce photoreceptor differentiation of hMSC (FGF2, taurine, retinoic acid, and insulin-like growth factor type1; FTRI), markedly upregulated the expression of components of the canonical Wnt signaling pathway, including WNT2B, DKK1, and active β-CATENIN. Although FTRI did not modify mRNA expression of WNT5B, a component of the noncanonical/planar cell polarity Wnt pathway, it upregulated its secretion. Furthermore, TGFβ1 not only decreased WNT2B expression, but also inhibited FTRI-induced photoreceptor differentiation of hMSC, as determined by expression of the photoreceptor markers NR2E3, RHODOPSIN, and RECOVERIN. Inhibition of TGFβ1 signaling by an ALK5 inhibitor prevented TGFβ1-induced changes in the expression of the two Wnt ligands examined. More importantly, inhibition of the canonical WNT signaling by XAV-939 prevented FTRI-induced photoreceptor differentiation. These observations suggest that TGFβ may play a key role in preventing neural differentiation of hMSC and may constitute a potential target for induction of endogenous regeneration of the human retina.
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Affiliation(s)
- Angshumonik Angbohang
- Division of Ocular Biology and Therapeutics, UCL Institute of Ophthalmology, London, United Kingdom
| | - Na Wu
- Division of Ocular Biology and Therapeutics, UCL Institute of Ophthalmology, London, United Kingdom
- Department of Ophthalmology and Visual Science, Eye & ENT Hospital, Shanghai Medical College, Fudan University, Shanghai, China
| | - Thalis Charalambous
- Division of Ocular Biology and Therapeutics, UCL Institute of Ophthalmology, London, United Kingdom
| | - Karen Eastlake
- Division of Ocular Biology and Therapeutics, UCL Institute of Ophthalmology, London, United Kingdom
| | - Yuan Lei
- Department of Ophthalmology and Visual Science, Eye & ENT Hospital, Shanghai Medical College, Fudan University, Shanghai, China
| | - Yung Su Kim
- Division of Ocular Biology and Therapeutics, UCL Institute of Ophthalmology, London, United Kingdom
| | - Xinghuai H. Sun
- Department of Ophthalmology and Visual Science, Eye & ENT Hospital, Shanghai Medical College, Fudan University, Shanghai, China
| | - G. Astrid Limb
- NIHR Biomedical Research Centre for Ophthalmology at Moorfields Eye Hospital and UCL Institute of Ophthalmology, London, United Kingdom
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Chang KC, Ponder J, Labarbera DV, Petrash JM. Aldose reductase inhibition prevents endotoxin-induced inflammatory responses in retinal microglia. Invest Ophthalmol Vis Sci 2014; 55:2853-61. [PMID: 24677107 DOI: 10.1167/iovs.13-13487] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
PURPOSE Retinal microglia become activated in diabetes and produce pro-inflammatory molecules associated with changes in retinal vasculature and increased apoptosis of retinal neurons and glial cells. We sought to determine if the action of aldose reductase (AR), an enzyme linked to the pathogenesis of diabetic retinopathy, contributes to activation of microglial cells. METHODS Involvement of AR in the activation process was studied using primary cultures of retinal microglia (RMG) isolated from wild-type and AR-null mice, or in mouse macrophage cultures treated with either AR inhibitors or small interfering RNA (siRNA) directed to AR. Inflammatory cytokines were measured by ELISA. Cell migration was measured using a transwell assay. Gelatin zymography was used to detect active matrix metalloproteinase (MMP)-9, while RMG-induced apoptosis of adult retinal pigment epithelium (ARPE-19) cells was studied in a cell coculture system. RESULTS Aldose reductase inhibition or genetic deficiency substantially reduced lipopolysacharide (LPS)-induced cytokine secretion from macrophages and RMG. Aldose reductase inhibition or deficiency also reduced the activation of MMP-9 and attenuated LPS-induced cell migration. Additionally, blockade of AR by sorbinil or through genetic means caused a reduction in the ability of activated RMG to induce apoptosis of ARPE-19 cells. CONCLUSIONS These results demonstrate that the action of AR contributes to the activation of RMG. Inhibition of AR may be a therapeutic strategy to reduce inflammation associated with activation of RMG in disease.
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Affiliation(s)
- Kun-Che Chang
- Department of Ophthalmology, School of Medicine, University of Colorado, Anschutz Medical Campus, Aurora, Colorado, United States
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