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Fang Y, Wang Q, Li Y, Zeng L, Liu J, Ou K. On implications of somatostatin in diabetic retinopathy. Neural Regen Res 2024; 19:1984-1990. [PMID: 38227526 DOI: 10.4103/1673-5374.390955] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2023] [Accepted: 10/10/2023] [Indexed: 01/17/2024] Open
Abstract
Somatostatin, a naturally produced neuroprotective peptide, depresses excitatory neurotransmission and exerts anti-proliferative and anti-inflammatory effects on the retina. In this review, we summarize the progress of somatostatin treatment of diabetic retinopathy through analysis of relevant studies published from February 2019 to February 2023 extracted from the PubMed and Google Scholar databases. Insufficient neuroprotection, which occurs as a consequence of declined expression or dysregulation of retinal somatostatin in the very early stages of diabetic retinopathy, triggers retinal neurovascular unit impairment and microvascular damage. Somatostatin replacement is a promising treatment for retinal neurodegeneration in diabetic retinopathy. Numerous pre-clinical and clinical trials of somatostatin analog treatment for early diabetic retinopathy have been initiated. In one such trial (EUROCONDOR), topical administration of somatostatin was found to exert neuroprotective effects in patients with pre-existing retinal neurodysfunction, but had no impact on the onset of diabetic retinopathy. Overall, we concluded that somatostatin restoration may be especially beneficial for the growing population of patients with early-stage retinopathy. In order to achieve early prevention of diabetic retinopathy initiation, and thereby salvage visual function before the appearance of moderate non-proliferative diabetic retinopathy, several issues need to be addressed. These include the needs to: a) update and standardize the retinal screening scheme to incorporate the detection of early neurodegeneration, b) identify patient subgroups who would benefit from somatostatin analog supplementation, c) elucidate the interactions of somatostatin, particularly exogenously-delivered somatostatin analogs, with other retinal peptides in the context of hyperglycemia, and d) design safe, feasible, low cost, and effective administration routes.
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Affiliation(s)
- Yanhong Fang
- Department of Ophthalmology, Chongqing University Jiangjin Hospital, Chongqing, China
| | - Qionghua Wang
- Department of Ophthalmology, Chongqing University Jiangjin Hospital, Chongqing, China
| | - Youjian Li
- College of Pharmacy, National & Local Joint Engineering Research Center of Targeted and Innovative Therapeutics, IATTI, Chongqing University of Arts and Sciences, Chongqing, China
| | - Li Zeng
- Shandong Provincial Hospital, Shandong Laboratory Animal Center, Science and Technology Innovation Center, Shandong First Medical University & Shandong Academy of Medical Sciences, Jinan, Shandong Province, China
| | - Jian Liu
- Academic Unit of Ophthalmology, Bristol Medical School, University of Bristol, Bristol, UK
| | - Kepeng Ou
- College of Pharmacy, National & Local Joint Engineering Research Center of Targeted and Innovative Therapeutics, IATTI, Chongqing University of Arts and Sciences, Chongqing, China
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2
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Zhang Q, Yan X, Han H, Wang Y, Sun J. Pericyte in retinal vascular diseases: A multifunctional regulator and potential therapeutic target. FASEB J 2024; 38:e23679. [PMID: 38780117 DOI: 10.1096/fj.202302624r] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2023] [Revised: 04/17/2024] [Accepted: 05/07/2024] [Indexed: 05/25/2024]
Abstract
Retinal vascular diseases (RVDs), in particular diabetic retinopathy, retinal vein occlusion, and retinopathy of prematurity, are leading contributors to blindness. The pathogenesis of RVD involves vessel dilatation, leakage, and occlusion; however, the specific underlying mechanisms remain unclear. Recent findings have indicated that pericytes (PCs), as critical members of the vascular mural cells, significantly contribute to the progression of RVDs, including detachment from microvessels, alteration of contractile and secretory properties, and excessive production of the extracellular matrix. Moreover, PCs are believed to have mesenchymal stem properties and, therefore, might contribute to regenerative therapy. Here, we review novel ideas concerning PC characteristics and functions in RVDs and discuss potential therapeutic strategies based on PCs, including the targeting of pathological signals and cell-based regenerative treatments.
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Affiliation(s)
- Quan Zhang
- Department of Ophthalmology, Eye Institute of Chinese PLA, Xijing Hospital, Air Force Medical University, Xi'an, China
- State Key Laboratory of Holistic Integrative Management of Gastrointestinal Cancers, Department of Biochemistry and Molecular Biology, Air Force Medical University, Xi'an, China
| | - Xianchun Yan
- State Key Laboratory of Holistic Integrative Management of Gastrointestinal Cancers, Department of Biochemistry and Molecular Biology, Air Force Medical University, Xi'an, China
| | - Hua Han
- State Key Laboratory of Holistic Integrative Management of Gastrointestinal Cancers, Department of Biochemistry and Molecular Biology, Air Force Medical University, Xi'an, China
| | - Yusheng Wang
- Department of Ophthalmology, Eye Institute of Chinese PLA, Xijing Hospital, Air Force Medical University, Xi'an, China
| | - Jiaxing Sun
- Department of Ophthalmology, Eye Institute of Chinese PLA, Xijing Hospital, Air Force Medical University, Xi'an, China
- Department of Neurobiology, Air Force Medical University, Xi'an, China
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3
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Reyes-Ortega P, Rodríguez-Arzate A, Noguez-Imm R, Arnold E, Thébault SC. Contribution of chemical and electrical transmission to the low delta-like intrinsic retinal oscillation in mice: A role for daylight-activated neuromodulators. Eur J Pharmacol 2024; 968:176384. [PMID: 38342360 DOI: 10.1016/j.ejphar.2024.176384] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2023] [Revised: 01/16/2024] [Accepted: 02/01/2024] [Indexed: 02/13/2024]
Abstract
Basal electroretinogram (ERG) oscillations have shown predictive value for modifiable risk factors for type 2 diabetes. However, their origin remains unknown. Here, we seek to establish the pharmacological profile of the low delta-like (δ1) wave in the mouse because it shows light sensitivity in the form of a decreased peak frequency upon photopic exposure. Applying neuropharmacological drugs by intravitreal injection, we eliminated the δ1 wave using lidocaine or by blocking all chemical and electrical synapses. The δ1 wave was insensitive to the blockade of photoreceptor input, but was accelerated when all inhibitory or ionotropic inhibitory receptors in the retina were antagonized. The sole blockade of GABAA, GABAB, GABAC, and glycine receptors also accelerated the δ1 wave. In contrast, the gap junction blockade slowed the δ1 wave. Both GABAA receptors and gap junctions contribute to the light sensitivity of the δ1 wave. We further found that the day light-activated neuromodulators dopamine and nitric oxide donors mimicked the effect of photopic exposure on the δ1 wave. All drug effects were validated through light flash-evoked ERG responses. Our data indicate that the low δ-like intrinsic wave detected by the non-photic ERG arises from an inner retinal circuit regulated by inhibitory neurotransmission and nitric oxide/dopamine-sensitive gap junction-mediated communication.
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Affiliation(s)
| | | | - Ramsés Noguez-Imm
- Laboratorio de Investigación Traslacional en Salud Visual D-13 y, Mexico
| | - Edith Arnold
- Laboratorio de Endocrinología Molecular A-14, Departamento de Neurobiología Celular y Molecular, Instituto de Neurobiología, Universidad Nacional Autónoma de México (UNAM), Campus UNAM-Juriquilla, 76230, Querétaro, Mexico; CONAHCYT-Instituto de Neurobiología, Universidad Nacional Autónoma de México (UNAM), Campus UNAM-Juriquilla, 76230 Querétaro, Mexico
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4
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Azrad-Leibovich T, Zahavi A, Gohas MF, Brookman M, Barinfeld O, Muhsinoglu O, Michowiz S, Fixler D, Goldenberg-Cohen N. Characterization of Diabetic Retinopathy in Two Mouse Models and Response to a Single Injection of Anti-Vascular Endothelial Growth Factor. Int J Mol Sci 2022; 24:ijms24010324. [PMID: 36613769 PMCID: PMC9820807 DOI: 10.3390/ijms24010324] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2022] [Revised: 12/06/2022] [Accepted: 12/20/2022] [Indexed: 12/28/2022] Open
Abstract
In this study, we characterized diabetic retinopathy in two mouse models and the response to anti-vascular endothelial growth factor (VEGF) injection. The study was conducted in 58 transgenic, non-obese diabetic (NOD) mice with spontaneous type 1 diabetes (n = 30, DMT1-NOD) or chemically induced (n = 28, streptozotocin, STZ-NOD) type 1 diabetes and 20 transgenic db/db mice with type 2 diabetes (DMT2-db/db); 30 NOD and 8 wild-type mice served as controls. Mice were examined at 21 days for vasculopathy, retinal thickness, and expression of genes involved in oxidative stress, angiogenesis, gliosis, and diabetes. The right eye was histologically examined one week after injection of bevacizumab, ranibizumab, saline, or no treatment. Flat mounts revealed microaneurysms and one apparent area of tufts of neovascularization in the diabetic retina. Immunostaining revealed activation of Müller glia and prominent Müller cells. Mean retinal thickness was greater in diabetic mice. RAGE increased and GFAP decreased in DMT1-NOD mice; GFAP and SOX-9 mildly increased in db/db mice. Anti-VEGF treatment led to reduced retinal thickness. Retinas showed vasculopathy and edema in DMT1-NOD and DMT2-db/db mice and activation of Müller glia in DMT1-NOD mice, with some response to anti-VEGF treatment. Given the similarity of diabetic retinopathy in mice and humans, comparisons of type 1 and type 2 diabetic mouse models may assist in the development of new treatment modalities.
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Affiliation(s)
- Tamar Azrad-Leibovich
- Krieger Eye Research Laboratory, Felsenstein Medical Research Center, Petach Tikva 4941492, Israel
- Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv 6997801, Israel
| | - Alon Zahavi
- Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv 6997801, Israel
- Department of Ophthalmology, Rabin Medical Center—Beilinson Hospital, Petach Tikva 4941492, Israel
- Laboratory of Eye Research, Felsenstein Medical Research Center, Petach Tikva 4941492, Israel
| | - Moran Friedman Gohas
- Krieger Eye Research Laboratory, Felsenstein Medical Research Center, Petach Tikva 4941492, Israel
- Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv 6997801, Israel
| | - Myles Brookman
- Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv 6997801, Israel
| | - Orit Barinfeld
- Krieger Eye Research Laboratory, Felsenstein Medical Research Center, Petach Tikva 4941492, Israel
- Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv 6997801, Israel
| | - Orkun Muhsinoglu
- Krieger Eye Research Laboratory, Felsenstein Medical Research Center, Petach Tikva 4941492, Israel
| | - Shalom Michowiz
- Department of Neurosurgery, Rabin Medical Center—Beilinson Hospital, Petach Tikva 4941492, Israel
| | - Dror Fixler
- Faculty of Engineering and Institute of Nanotechonology and Advanced Materials, Bar Ilan University, Ramat Gan 5200100, Israel
| | - Nitza Goldenberg-Cohen
- Krieger Eye Research Laboratory, Felsenstein Medical Research Center, Petach Tikva 4941492, Israel
- Department of Ophthalmology, Bnai Zion Medical Center of Israel, Haifa 3339419, Israel
- Bruce and Ruth Rappaport Faculty of Medicine, Israel Institute of Technology—Technion, Haifa 3200003, Israel
- Correspondence: ; Tel.: +97-(24)-8359554
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Connexins Signatures of the Neurovascular Unit and Their Physio-Pathological Functions. Int J Mol Sci 2022; 23:ijms23179510. [PMID: 36076908 PMCID: PMC9455936 DOI: 10.3390/ijms23179510] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2022] [Revised: 08/19/2022] [Accepted: 08/21/2022] [Indexed: 11/16/2022] Open
Abstract
Central nervous system (CNS) homeostasis is closely linked to the delicate balance of the microenvironment in which different cellular components of the neurovascular unit (NVU) coexist. Intercellular communication plays a pivotal role in exchanges of signaling molecules and mediators essential for survival functions, as well as in the removal of disturbing elements that can lead to related pathologies. The specific signatures of connexins (Cxs), proteins which form either gap junctions (GJs) or hemichannels (HCs), represent the biological substrate of the pathophysiological balance. Connexin 43 (Cx43) is undoubtedly one of the most important factors in glia–neuro–vascular crosstalk. Herein, Cxs signatures of every NVU component are highlighted and their critical influence on functional processes in healthy and pathological conditions of nervous microenvironment is reviewed.
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Chen J, Sun Y, Chen L, Zhou Y. NADH-Cytochrome B5 reductase 2 suppresses retinal vascular dysfunction through regulation of vascular endothelial growth factor A in diabetic retinopathy. Exp Eye Res 2022; 222:109186. [PMID: 35820466 DOI: 10.1016/j.exer.2022.109186] [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: 02/10/2022] [Revised: 06/07/2022] [Accepted: 07/05/2022] [Indexed: 11/04/2022]
Abstract
Diabetic retinopathy (DR) is a progressive vascular complication of diabetes mellitus (DM) and is related to retinal vascular abnormalities. NADH-Cytochrome B5 Reductase 2 (CBR2) has been implicated in angiogenesis, but the effect of CBR2 on angiogenesis and endothelial cell biological behavior in DR remains unclear. Here, we aimed to explore the effect of CBR2 on retinal vascular dysfunction under diabetic conditions. The histological analyses were performed to explore the effect of CBR2 on pathological change in streptozotocin (STZ)-induced diabetic rat retinas. The effect of CBR2 on endothelial cell function was explored by CCK-8, scratch wound, transwell, tube formation, and immunofluorescence assays in high glucose (HG)-stimulated human retinal microvascular endothelial cells (HRMECs). CBR2 expression was significantly downregulated in DM rat retinas and HG-stimulated HRMECs. Intravitreal injection of CBR2-expressing lentivirus under diabetic conditions reduced retinal angiogenesis, acellular capillary formation, and pericyte loss, along with decreased expression of hypoxia-inducible factor-1α (HIF-1α), cluster of differentiation 31 (CD31), and vascular endothelial growth factor A (VEGFA) in vivo. Moreover, CBR2 overexpression inhibited cell growth and tube formation and led to decreased expression of HIF-1α and VEGFA in HG-induced HRMECs. Interestingly, the repressive effects of CBR2 on cell proliferation, migration, and tube formation under HG conditions were strongly reversed when VEGFA was overexpressed. Overall, the key findings of our study suggested that CBR2 might alleviate retinal vascular dysfunction and abnormal endothelial proliferation during the process of DR by regulating VEGFA, providing a piece of potent evidence for DR therapy.
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Affiliation(s)
- Jun Chen
- Department of Ophthalmology, The First Hospital of China Medical University, Shenyang, Liaoning, PR China
| | - Yizhou Sun
- Department of Ophthalmology, The First Hospital of China Medical University, Shenyang, Liaoning, PR China
| | - Lei Chen
- Department of Ophthalmology, The First Hospital of China Medical University, Shenyang, Liaoning, PR China
| | - Yun Zhou
- Department of Ophthalmology, The First Hospital of China Medical University, Shenyang, Liaoning, PR China.
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Chatziralli I, Touhami S, Cicinelli MV, Agapitou C, Dimitriou E, Theodossiadis G, Theodossiadis P. Disentangling the association between retinal non-perfusion and anti-VEGF agents in diabetic retinopathy. Eye (Lond) 2022; 36:692-703. [PMID: 34408316 PMCID: PMC8956693 DOI: 10.1038/s41433-021-01750-4] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2021] [Revised: 07/29/2021] [Accepted: 08/06/2021] [Indexed: 02/07/2023] Open
Abstract
Diabetic retinopathy (DR) is the most common microvascular complication of diabetes mellitus (DM) and the leading cause of blindness in patients with DM. In the pathogenesis of DR, chronic hyperglycemia leads to biochemical and structural alterations in retinal blood vessels' wall, resulting in hyperpermeability and non-perfusion. Since vascular endothelial growth factor (VEGF) has been found to play a significant role in the pathogenesis of DR, this review sheds light on the effect of intravitreal anti-VEGF agents on retinal non-perfusion in patients with DR. Based on the existing literature, anti-VEGF agents have been shown to improve DR severity, although they cannot reverse retinal ischemia. The results of the published studies are controversial and differ based on the location of retinal non-perfusion, as well as the imaging modality used to assess retinal non-perfusion. In cases of macular non-perfusion, most of studies showed no change in both fundus fluorescein angiography (FFA) and optical coherence tomography (OCTA) in patients with DR treated with intravitreal anti-VEGF agents, while few studies reported worsening of non-perfusion with enlargement of foveal avascular zone (FAZ). Regarding peripheral ischemia, studies using wide-field-FFA demonstrated an improvement or stability in non-perfusion areas after anti-VEGF treatment. However, the use of wide-field-OCTA revealed no signs of re-perfusion of retinal vessels post anti-VEGF treatment. Further prospective studies with long follow-up and large sample size are still needed to draw solid conclusions.
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Affiliation(s)
- Irini Chatziralli
- grid.5216.00000 0001 2155 08002nd Department of Ophthalmology, National and Kapodistrian University of Athens, Athens, Greece
| | - Sara Touhami
- grid.462844.80000 0001 2308 1657Department of Ophthalmology, Reference Center in Rare diseases, DHU Sight Restore, Hôpital Pitié Salpêtrière, Sorbonne Université, Paris, France
| | - Maria Vittoria Cicinelli
- grid.15496.3f0000 0001 0439 0892School of Medicine, Vita-Salute San Raffaele University, Milan, Italy ,grid.18887.3e0000000417581884Department of Ophthalmology, IRCCS San Raffaele Scientific Institute, Milan, Italy
| | - Chrysa Agapitou
- grid.5216.00000 0001 2155 08002nd Department of Ophthalmology, National and Kapodistrian University of Athens, Athens, Greece
| | - Eleni Dimitriou
- grid.5216.00000 0001 2155 08002nd Department of Ophthalmology, National and Kapodistrian University of Athens, Athens, Greece
| | - George Theodossiadis
- grid.5216.00000 0001 2155 08002nd Department of Ophthalmology, National and Kapodistrian University of Athens, Athens, Greece
| | - Panagiotis Theodossiadis
- grid.5216.00000 0001 2155 08002nd Department of Ophthalmology, National and Kapodistrian University of Athens, Athens, Greece
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Atef MM, Shafik NM, Hafez YM, Watany MM, Selim A, Shafik HM, Safwat El-Deeb O. The evolving role of long noncoding RNA HIF1A-AS2 in diabetic retinopathy: a cross-link axis between hypoxia, oxidative stress and angiogenesis via MAPK/VEGF-dependent pathway. Redox Rep 2022; 27:70-78. [PMID: 35285425 PMCID: PMC8928809 DOI: 10.1080/13510002.2022.2050086] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
Abstract
Background Diabetic retinopathy (DR) signifies a frequent serious diabetic complication influencing retinal structure and function. Dysregulation of lncRNAs drives a wide array of human diseases especially diabetes; thus, we aimed to study lncRNA HIF1A-AS2 role and its interplay with hypoxia, oxidative stress (OS), and angiogenesis in DR. Materials and methods 60 DM patients in addition to 15 healthy subjects. were enrolled. LncRNA HIF1A-AS2 mRNA relative gene expression was assessed. Hypoxia inducible factor 1-alpha (HIF-1α), vascular endothelial growth factor (VEGF), mitogen activated protein kinase (MAPK), and endoglin levels were assessed. Detection of DNA damage using comet assay, and Redox status parameters were also detected. Results LncRNA HIF1A-AS2 expression was significantly increased in diabetic patients with the highest levels in proliferative DR patients. Moreover, HIFα, VEGF, MAPK, and Endogolin levels were significantly higher in the diabetic patients compared to control group with the highest levels in in proliferative DR patients. Significant DNA damage in comet assay was observed to be the highest in this group. Conclusion We observed for the first time the imminent role of long noncoding RNA HIF1A-AS2 in DR throughout its stages and its interplay with hypoxia, OS, and angiogenesis via MAPK/VEGF-dependent pathway.
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Affiliation(s)
- Marwa Mohamed Atef
- Medical Biochemistry Department, Faculty of Medicine, Tanta University, Tanta, Egypt
| | - Noha M. Shafik
- Medical Biochemistry Department, Faculty of Medicine, Tanta University, Tanta, Egypt
| | - Yasser Mostafa Hafez
- Internal Medicine Department, Faculty of Medicine, Tanta University, Tanta, Egypt
| | - Mona Mohamed Watany
- Clinical pathology Department, Faculty of Medicine, Tanta University, Tanta, Egypt
| | - Amal Selim
- Internal Medicine Department, Faculty of Medicine, Tanta University, Tanta, Egypt
| | - Heba M. Shafik
- Ophthalmology Department, Faculty of Medicine, Tanta University, Tanta, Egypt
| | - Omnia Safwat El-Deeb
- Medical Biochemistry Department, Faculty of Medicine, Tanta University, Tanta, Egypt
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Du X, Yang L, Kong L, Sun Y, Shen K, Cai Y, Sun H, Zhang B, Guo S, Zhang A, Wang X. Metabolomics of various samples advancing biomarker discovery and pathogenesis elucidation for diabetic retinopathy. Front Endocrinol (Lausanne) 2022; 13:1037164. [PMID: 36387907 PMCID: PMC9646596 DOI: 10.3389/fendo.2022.1037164] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/05/2022] [Accepted: 10/10/2022] [Indexed: 11/28/2022] Open
Abstract
Diabetic retinopathy (DR) is a universal microvascular complication of diabetes mellitus (DM), which is the main reason for global sight damage/loss in middle-aged and/or older people. Current clinical analyses, like hemoglobin A1c, possess some importance as prognostic indicators for DR severity, but no effective circulating biomarkers are used for DR in the clinic currently, and studies on the latent pathophysiology remain lacking. Recent developments in omics, especially metabolomics, continue to disclose novel potential biomarkers in several fields, including but not limited to DR. Therefore, based on the overview of metabolomics, we reviewed progress in analytical technology of metabolomics, the prominent roles and the current status of biomarkers in DR, and the update of potential biomarkers in various DR-related samples via metabolomics, including tear as well as vitreous humor, aqueous humor, retina, plasma, serum, cerebrospinal fluid, urine, and feces. In this review, we underscored the in-depth analysis and elucidation of the common biomarkers in different biological samples based on integrated results, namely, alanine, lactate, and glutamine. Alanine may participate in and regulate glucose metabolism through stimulating N-methyl-D-aspartate receptors and subsequently suppressing insulin secretion, which is the potential pathogenesis of DR. Abnormal lactate could cause extensive oxidative stress and neuroinflammation, eventually leading to retinal hypoxia and metabolic dysfunction; on the other hand, high-level lactate may damage the structure and function of the retinal endothelial cell barrier via the G protein-coupled receptor 81. Abnormal glutamine indicates a disturbance of glutamate recycling, which may affect the activation of Müller cells and proliferation via the PPP1CA-YAP-GS-Gln-mTORC1 pathway.
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Affiliation(s)
- Xiaohui Du
- National Chinmedomics Research Center, National TCM Key Laboratory of Serum Pharmacochemistry, Metabolomics Laboratory, Department of Pharmaceutical Analysis, Heilongjiang University of Chinese Medicine, Harbin, China
| | - Le Yang
- State Key Laboratory of Dampness Syndrome, the Second Affiliated Hospital Guangzhou University of Chinese Medicine, Guangzhou, China
| | - Ling Kong
- National Chinmedomics Research Center, National TCM Key Laboratory of Serum Pharmacochemistry, Metabolomics Laboratory, Department of Pharmaceutical Analysis, Heilongjiang University of Chinese Medicine, Harbin, China
| | - Ye Sun
- National Chinmedomics Research Center, National TCM Key Laboratory of Serum Pharmacochemistry, Metabolomics Laboratory, Department of Pharmaceutical Analysis, Heilongjiang University of Chinese Medicine, Harbin, China
- State Key Laboratory of Dampness Syndrome, the Second Affiliated Hospital Guangzhou University of Chinese Medicine, Guangzhou, China
| | - Kunshuang Shen
- National Chinmedomics Research Center, National TCM Key Laboratory of Serum Pharmacochemistry, Metabolomics Laboratory, Department of Pharmaceutical Analysis, Heilongjiang University of Chinese Medicine, Harbin, China
| | - Ying Cai
- National Chinmedomics Research Center, National TCM Key Laboratory of Serum Pharmacochemistry, Metabolomics Laboratory, Department of Pharmaceutical Analysis, Heilongjiang University of Chinese Medicine, Harbin, China
| | - Hui Sun
- National Chinmedomics Research Center, National TCM Key Laboratory of Serum Pharmacochemistry, Metabolomics Laboratory, Department of Pharmaceutical Analysis, Heilongjiang University of Chinese Medicine, Harbin, China
- *Correspondence: Hui Sun, ; Xijun Wang,
| | - Bo Zhang
- National Chinmedomics Research Center, National TCM Key Laboratory of Serum Pharmacochemistry, Metabolomics Laboratory, Department of Pharmaceutical Analysis, Heilongjiang University of Chinese Medicine, Harbin, China
| | - Sifan Guo
- National Chinmedomics Research Center, National TCM Key Laboratory of Serum Pharmacochemistry, Metabolomics Laboratory, Department of Pharmaceutical Analysis, Heilongjiang University of Chinese Medicine, Harbin, China
| | - Aihua Zhang
- National Chinmedomics Research Center, National TCM Key Laboratory of Serum Pharmacochemistry, Metabolomics Laboratory, Department of Pharmaceutical Analysis, Heilongjiang University of Chinese Medicine, Harbin, China
| | - Xijun Wang
- National Chinmedomics Research Center, National TCM Key Laboratory of Serum Pharmacochemistry, Metabolomics Laboratory, Department of Pharmaceutical Analysis, Heilongjiang University of Chinese Medicine, Harbin, China
- State Key Laboratory of Dampness Syndrome, the Second Affiliated Hospital Guangzhou University of Chinese Medicine, Guangzhou, China
- State Key Laboratory of Quality Research in Chinese Medicine, Macau University of Science and Technology, Macau, Macau SAR, China
- *Correspondence: Hui Sun, ; Xijun Wang,
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