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Morya AK, Ramesh PV, Nishant P, Kaur K, Gurnani B, Heda A, Salodia S. Diabetic retinopathy: A review on its pathophysiology and novel treatment modalities. World J Methodol 2024; 14:95881. [DOI: 10.5662/wjm.v14.i4.95881] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/21/2024] [Revised: 05/28/2024] [Accepted: 07/10/2024] [Indexed: 07/26/2024] Open
Abstract
Diabetes mellitus (DM) is a chronic metabolic non-communicable disease with the ability to cause serious microvascular and macrovascular complications throughout the body, including in the eye. Diabetic retinopathy (DR), present in one-third of patients with diabetes, is a vision-threatening complication caused by uncontrolled diabetes, which greatly affects the retinal blood vessels and the light-sensitive inner retina, eventually leading to blindness. Several epidemiological studies elucidate that DR can vary by age of onset, duration, types of diabetes, and ethnicity. Recent studies show that the pathogenesis of diabetic retinopathy has spread its roots beyond merely being the result of hyperglycemia. The complexity of its etiopathology and diagnosis makes therapeutic intervention challenging. This review throws light on the pathological processes behind DR, the cascade of events that follow it, as well as the available and emerging treatment options.
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Affiliation(s)
- Arvind Kumar Morya
- Head of the Department, Department of Ophthalmology, All India Institute of Medical Sciences, Hyderabad 508126, Telangana, India
| | - Prasanna Venkatesh Ramesh
- Glaucoma Medical Officer, Department of Glaucoma and Research, Mahathma Eye Hospital Private Limited, Trichy 620017, Tamil Nadu, India
| | - Prateek Nishant
- Department of Ophthalmology, ESIC Medical College, Patna 801103, Bihar, India
| | - Kirandeep Kaur
- Department of Pediatric Ophthalmology and Strabismus, Gomabai Netralaya and Research Centre, Neemuch 458441, Madhya Pradesh, India
| | - Bharat Gurnani
- Cornea and Refractive Services, Gomabai Netralaya and Research Centre, Neemuch 458441, Madhya Pradesh, India
| | - Aarti Heda
- Department of Ophthalmology, National Institute of Ophthalmology, Pune 411000, Maharashtra, India
| | - Sarika Salodia
- Global Medical Safety, Lundbeck, Singapore 569933, Singapore, Singapore
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Hartnett ME, Fickweiler W, Adamis AP, Brownlee M, Das A, Duh EJ, Feener EP, King G, Kowluru R, Luhmann UF, Storti F, Wykoff CC, Aiello LP. Rationale of Basic and Cellular Mechanisms Considered in Updating the Staging System for Diabetic Retinal Disease. OPHTHALMOLOGY SCIENCE 2024; 4:100521. [PMID: 39006804 PMCID: PMC11245984 DOI: 10.1016/j.xops.2024.100521] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Received: 01/04/2024] [Revised: 03/12/2024] [Accepted: 03/18/2024] [Indexed: 07/16/2024]
Abstract
Purpose Hyperglycemia is a major risk factor for early lesions of diabetic retinal disease (DRD). Updating the DRD staging system to incorporate relevant basic and cellular mechanisms pertinent to DRD is necessary to better address early disease, disease progression, the use of therapeutic interventions, and treatment effectiveness. Design We sought to review preclinical and clinical evidence on basic and cellular mechanisms potentially pertinent to DRD that might eventually be relevant to update the DRD staging system. Participants Not applicable. Methods The Basic and Cellular Mechanisms Working Group (BCM-WG) of the Mary Tyler Moore Vision Initiative carefully and extensively reviewed available preclinical and clinical evidence through multiple iterations and classified these. Main Outcome Measures Classification was made into evidence grids, level of supporting evidence, and anticipated future relevance to DRD. Results A total of 40 identified targets based on pathophysiology and other parameters for DRD were grouped into concepts or evaluated as specific candidates. VEGFA, peroxisome proliferator-activated receptor-alpha related pathways, plasma kallikrein, and angiopoietin 2 had strong agreement as promising for use as biomarkers in diagnostic, monitoring, predictive, prognostic, and pharmacodynamic responses as well as for susceptibility/risk biomarkers that could underlie new assessments and eventually be considered within an updated DRD staging system or treatment, based on the evidence and need for research that would fit within a 2-year timeline. The BCM-WG found there was strong reason also to pursue the following important concepts regarding scientific research of DRD acknowledging their regulation by hyperglycemia: inflammatory/cytokines, oxidative signaling, vasoprotection, neuroprotection, mitophagy, and nutrients/microbiome. Conclusion Promising targets that might eventually be considered within an updated DRD staging system or treatment were identified. Although the BCM-WG recognizes that at this stage little can be incorporated into a new DRD staging system, numerous potential targets and important concepts deserve continued support and research, as they may eventually serve as biomarkers and/or therapeutic targets with measurable benefits to patients with diabetes. Financial Disclosures Proprietary or commercial disclosure may be found in the Footnotes and Disclosures at the end of this article.
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Affiliation(s)
- M. Elizabeth Hartnett
- Department of Ophthalmology, Byers Eye Institute of Stanford University, Palo Alto, California
| | - Ward Fickweiler
- Research Division, Joslin Diabetes Center, Harvard Medical School, Boston, Massachusetts
- Beetham Eye Institute, Joslin Diabetes Center, Boston, Massachusetts
- Department of Ophthalmology, Harvard Medical School, Boston, Massachusetts
| | - Anthony P. Adamis
- Department of Ophthalmology, Harvard Medical School, Boston, Massachusetts
- Department of Medicine, Harvard Medical School, Boston, Massachusetts
| | - Michael Brownlee
- Departments of Medicine and Pathology, Einstein Diabetes Research Center, Albert Einstein College of Medicine, Bronx, New York
| | - Arup Das
- Department of Surgery, University of New Mexico School of Medicine, Albuquerque, New Mexico
| | - Elia J. Duh
- Department of Ophthalmology, Johns Hopkins University School of Medicine, Baltimore, Maryland
| | - Edward P. Feener
- Research Division, KalVista Pharmaceuticals, Inc, Cambridge, Massachusetts
| | - George King
- Research Division, Joslin Diabetes Center, Harvard Medical School, Boston, Massachusetts
- Department of Ophthalmology, Harvard Medical School, Boston, Massachusetts
- Department of Medicine, Harvard Medical School, Boston, Massachusetts
| | - Renu Kowluru
- Department of Ophthalmology, Visual & Anatomical Sciences, Wayne State University, Detroit, Michigan
| | - Ulrich F.O. Luhmann
- Roche Pharmaceutical Research and Early Development, Translational Medicine Ophthalmology, Roche Innovation Center Basel, Basel, Switzerland
| | - Federica Storti
- Roche Pharmaceutical Research and Early Development, Translational Medicine Ophthalmology, Roche Innovation Center Basel, Basel, Switzerland
| | - Charles C. Wykoff
- Ophthalmology, Retina Consultants of Texas, Houston, Texas
- Blanton Eye Institute, Houston Methodist Hospital, Houston, Texas
| | - Lloyd Paul Aiello
- Research Division, Joslin Diabetes Center, Harvard Medical School, Boston, Massachusetts
- Beetham Eye Institute, Joslin Diabetes Center, Boston, Massachusetts
- Department of Ophthalmology, Harvard Medical School, Boston, Massachusetts
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Serikbaeva A, Li Y, Ma S, Yi D, Kazlauskas A. Resilience to diabetic retinopathy. Prog Retin Eye Res 2024; 101:101271. [PMID: 38740254 PMCID: PMC11262066 DOI: 10.1016/j.preteyeres.2024.101271] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2022] [Revised: 05/03/2024] [Accepted: 05/10/2024] [Indexed: 05/16/2024]
Abstract
Chronic elevation of blood glucose at first causes relatively minor changes to the neural and vascular components of the retina. As the duration of hyperglycemia persists, the nature and extent of damage increases and becomes readily detectable. While this second, overt manifestation of diabetic retinopathy (DR) has been studied extensively, what prevents maximal damage from the very start of hyperglycemia remains largely unexplored. Recent studies indicate that diabetes (DM) engages mitochondria-based defense during the retinopathy-resistant phase, and thereby enables the retina to remain healthy in the face of hyperglycemia. Such resilience is transient, and its deterioration results in progressive accumulation of retinal damage. The concepts that co-emerge with these discoveries set the stage for novel intellectual and therapeutic opportunities within the DR field. Identification of biomarkers and mediators of protection from DM-mediated damage will enable development of resilience-based therapies that will indefinitely delay the onset of DR.
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Affiliation(s)
- Anara Serikbaeva
- Department of Physiology and Biophysics, University of Illinois at Chicago, 1905 W Taylor St, Chicago, IL 60612, USA
| | - Yanliang Li
- Department of Ophthalmology and Visual Sciences, University of Illinois at Chicago, 1905 W Taylor St, Chicago, IL 60612, USA
| | - Simon Ma
- Department of Bioengineering, University of Illinois at Chicago, 1905 W Taylor St, Chicago, IL 60612, USA
| | - Darvin Yi
- Department of Ophthalmology and Visual Sciences, University of Illinois at Chicago, 1905 W Taylor St, Chicago, IL 60612, USA; Department of Bioengineering, University of Illinois at Chicago, 1905 W Taylor St, Chicago, IL 60612, USA
| | - Andrius Kazlauskas
- Department of Physiology and Biophysics, University of Illinois at Chicago, 1905 W Taylor St, Chicago, IL 60612, USA; Department of Ophthalmology and Visual Sciences, University of Illinois at Chicago, 1905 W Taylor St, Chicago, IL 60612, USA.
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Kumar J, Kowluru RA. Mitochondrial DNA transcription and mitochondrial genome-encoded long noncoding RNA in diabetic retinopathy. Mitochondrion 2024; 78:101925. [PMID: 38944370 DOI: 10.1016/j.mito.2024.101925] [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: 02/14/2024] [Revised: 06/13/2024] [Accepted: 06/26/2024] [Indexed: 07/01/2024]
Abstract
In diabetic retinopathy, mitochondrial DNA (mtDNA) is damaged and mtDNA-encoded genes and long noncoding RNA cytochrome B (LncCytB) are downregulated. LncRNAs lack an open reading frame, but they can regulate gene expression by associating with DNA/RNA/protein. Double stranded mtDNA has promoters on both heavy (HSP) and light (LSP) strands with binding sites for mitochondrial transcription factor A (TFAM) between them. The aim was to investigate the role of LncCytB in mtDNA transcription in diabetic retinopathy. Using human retinal endothelial cells incubated in high glucose, the effect of regulation of LncCytB on TFAM binding at mtDNA promoters was investigated by Chromatin immunoprecipitation, and binding of LncCytB at TFAM by RNA immunoprecipitation and RNA fluorescence in situ hybridization. High glucose decreased TFAM binding at both HSP and LSP, and binding of LncCytB at TFAM. While LncCytB overexpression ameliorated decrease in TFAM binding and transcription of genes encoded by both H- and L- strands, LncCytB-siRNA further downregulated them. Maintenance of mitochondrial homeostasis by overexpressing mitochondrial superoxide dismutase or Sirtuin-1 protected diabetes-induced decrease in TFAM binding at mtDNA and LncCytB binding at TFAM, and mtDNA transcription. Similar results were obtained from mouse retinal microvessels from streptozotocin-induced diabetic mice. Thus, LncCytB facilitates recruitment of TFAM at HSP and LSP, and its downregulation in diabetes compromises the binding, resulting in the downregulation of polypeptides encoded by mtDNA. Regulation of LncCytB, in addition to protecting mitochondrial genomic stability, should also help in maintaining the transcription of mtDNA encoded genes and electron transport chain integrity in diabetic retinopathy.
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Affiliation(s)
- Jay Kumar
- Ophthalmology, Visual and Anatomical Sciences, Wayne State University, 4717 St. Antoine, Detroit, MI 48201, USA
| | - Renu A Kowluru
- Ophthalmology, Visual and Anatomical Sciences, Wayne State University, 4717 St. Antoine, Detroit, MI 48201, USA.
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Guo HQ, Xue R, Wan G. Identification of biomarkers associated with ferroptosis in diabetic retinopathy based on WGCNA and machine learning. Front Genet 2024; 15:1376771. [PMID: 38863444 PMCID: PMC11165058 DOI: 10.3389/fgene.2024.1376771] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2024] [Accepted: 05/10/2024] [Indexed: 06/13/2024] Open
Abstract
Objective: Diabetic retinopathy (DR) is a chronic progressive eye disease that affects millions of diabetic patients worldwide, and ferroptosis may contribute to the underlying mechanisms of DR. The main objective of this work is to explore key genes associated with ferroptosis in DR and to determine their feasibility as diagnostic markers. Methods: WGCNA identify the most relevant signature modules in DR. Machine learning methods were used to de-screen the feature genes. ssGSEA calculated the scoring of immune cells in the DR versus control samples and compared the associations with the core genes by Spearman correlation. Results: We identified 2,897 differential genes in DR versus normal samples. WGCNA found tan module to have the highest correlation with DR patients. Finally, 20 intersecting genes were obtained from differential genes, tan module and iron death genes, which were screened by LASSO and SVM-RFE method, and together identified 6 genes as potential diagnostic markers. qPCR verified the expression and ROC curves confirmed the diagnostic accuracy of the 6 genes. In addition, our ssGSEA scoring identified these 6 core genes as closely associated with immune infiltrating cells. Conclusion: In conclusion, we analyzed for the first time the potential link of iron death in the pathogenesis of DR. This has important implications for future studies of iron death-mediated pro-inflammatory immune mechanisms.
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Affiliation(s)
| | | | - Guangming Wan
- Department of Ophthalmology, First Affiliated Hospital of Zhengzhou University, Henan Province Eye Hospital, Zhengzhou, China
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Qiao Q, Liu X, Xue W, Chen L, Hou X. Analysis of the association between high antioxidant diet and lifestyle habits and diabetic retinopathy based on NHANES cross-sectional study. Sci Rep 2024; 14:11868. [PMID: 38789523 PMCID: PMC11126608 DOI: 10.1038/s41598-024-62707-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2024] [Accepted: 05/21/2024] [Indexed: 05/26/2024] Open
Abstract
Oxidative stress plays a crucial role in increasing the risk of developing diabetic retinopathy (DR). The oxidative balance score (OBS) and the composite dietary antioxidant index (CDAI) are two tools for assessing the effects of diet and lifestyle on oxidative stress. The aim of this study was to investigate the association between OBS, CDAI and the occurrence of DR. After controlling for potential confounders, OBS was negatively associated with DR with an odds ratio (OR) of 0.976 and a 95% confidence interval (CI) of 0.956-0.996, suggesting that for every unit increase in OBS, the risk of DR was reduced by 2.4%. In contrast, the relationship between OBS and CDAI was not significant (P > 0.05), suggesting that it was OBS, not CDAI, that contributed to the reduced risk of diabetic retinopathy. After adjusting for potential confounders, OBS was negatively associated with DR (OR: 0.976; 95% CI 0.956-0.996), but this association was not found in CDAI (P > 0.05), suggesting that for every one-unit increase in OBS, there was a 2.4% reduction in the risk of developing DR. This study suggests that a diet and lifestyle high in OBS reduces the risk of developing DR, which provides a rationale for nutritional interventions to prevent DR.
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Affiliation(s)
- Qincheng Qiao
- Department of Endocrinology and Metabolism, Qilu Hospital of Shandong University, Jinan, 250012, Shandong, People's Republic of China
- The First Clinical Medical College, Cheeloo College of Medicine, Shandong University, Jinan, China
| | - Xingjian Liu
- The First Clinical Medical College, Cheeloo College of Medicine, Shandong University, Jinan, China
| | - Wen Xue
- Department of Endocrinology and Metabolism, Qilu Hospital of Shandong University, Jinan, 250012, Shandong, People's Republic of China
| | - Li Chen
- Department of Endocrinology and Metabolism, Qilu Hospital of Shandong University, Jinan, 250012, Shandong, People's Republic of China
- Institute of Endocrine and Metabolic Diseases of Shandong University, Jinan, 250012, China
- Key Laboratory of Endocrine and Metabolic Diseases, Shandong Province Medicine and Health, Jinan, China
- Jinan Clinical Research Center for Endocrine and Metabolic Diseases, Jinan, China
| | - Xinguo Hou
- Department of Endocrinology and Metabolism, Qilu Hospital of Shandong University, Jinan, 250012, Shandong, People's Republic of China.
- Institute of Endocrine and Metabolic Diseases of Shandong University, Jinan, 250012, China.
- Key Laboratory of Endocrine and Metabolic Diseases, Shandong Province Medicine and Health, Jinan, China.
- Jinan Clinical Research Center for Endocrine and Metabolic Diseases, Jinan, China.
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Sadikan MZ, Abdul Nasir NA, Ibahim MJ, Iezhitsa I, Agarwal R. Identifying the stability of housekeeping genes to be used for the quantitative real-time PCR normalization in retinal tissue of streptozotocin-induced diabetic rats. Int J Ophthalmol 2024; 17:794-805. [PMID: 38766348 PMCID: PMC11074185 DOI: 10.18240/ijo.2024.05.02] [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: 08/03/2023] [Accepted: 02/23/2024] [Indexed: 05/22/2024] Open
Abstract
AIM To investigate the stability of the seven housekeeping genes: beta-actin (ActB), glyceraldehyde-3-phosphate dehydrogenase (GAPDH), 18s ribosomal unit 5 (18s), cyclophilin A (CycA), hypoxanthine-guanine phosphoribosyl transferase (HPRT), ribosomal protein large P0 (36B4) and terminal uridylyl transferase 1 (U6) in the diabetic retinal tissue of rat model. METHODS The expression of these seven genes in rat retinal tissues was determined using real-time quantitative reverse transcription polymerase chain reaction (RT-qPCR) in two groups; normal control rats and streptozotocin-induced diabetic rats. The stability analysis of gene expression was investigated using geNorm, NormFinder, BestKeeper, and comparative delta-Ct (ΔCt) algorithms. RESULTS The 36B4 gene was stably expressed in the retinal tissues of normal control animals; however, it was less stable in diabetic retinas. The 18s gene was expressed consistently in both normal control and diabetic rats' retinal tissue. That this gene was the best reference for data normalisation in RT-qPCR studies that used the retinal tissue of streptozotocin-induced diabetic rats. Furthermore, there was no ideal gene stably expressed for use in all experimental settings. CONCLUSION Identifying relevant genes is a need for achieving RT-qPCR validity and reliability and must be appropriately achieved based on a specific experimental setting.
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Affiliation(s)
- Muhammad Zulfiqah Sadikan
- Department of Pharmacology, Faculty of Medicine, Manipal University College Malaysia (MUCM), Bukit Baru, Melaka 75150, Malaysia
| | - Nurul Alimah Abdul Nasir
- Centre for Neuroscience Research (NeuRon), Faculty of Medicine, Universiti Teknologi MARA, Sungai Buloh Campus, Sungai Buloh, Selangor 47000, Malaysia
- Department of Medical Education, Faculty of Medicine, Universiti Teknologi MARA, Sungai Buloh Campus, Sungai Buloh, Selangor 47000, Malaysia
| | - Mohammad Johari Ibahim
- Department of Biochemistry and Molecular Medicine, Faculty of Medicine, Universiti Teknologi MARA, Sungai Buloh Campus, Sungai Buloh, Selangor 47000, Malaysia
| | - Igor Iezhitsa
- School of Medicine, International Medical University, Bukit Jalil, Kuala Lumpur 57000, Malaysia
- Department of Pharmacology and Bioinformatics, Volgograd State Medical University, Volgograd 400131, Russia
| | - Renu Agarwal
- School of Medicine, International Medical University, Bukit Jalil, Kuala Lumpur 57000, Malaysia
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Cappellani F, Regillo CD, Haller JA, Gagliano C, Pulido JS. Exploring the Associated Genetic Causes of Diabetic Retinopathy as a Model of Inflammation in Retinal Diseases. Int J Mol Sci 2024; 25:5456. [PMID: 38791494 PMCID: PMC11121794 DOI: 10.3390/ijms25105456] [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: 02/28/2024] [Revised: 04/24/2024] [Accepted: 04/29/2024] [Indexed: 05/26/2024] Open
Abstract
To investigate potential biomarkers and biological processes associated with diabetic retinopathy (DR) using transcriptomic and proteomic data. The OmicsPred PheWAS application was interrogated to identify genes and proteins associated with DR and diabetes mellitus (DM) at a false discovery rate (FDR)-adjusted p-value of <0.05 and also <0.005. Gene Ontology PANTHER analysis and STRING database analysis were conducted to explore the biological processes and protein interactions related to the identified biomarkers. The interrogation identified 49 genes and 22 proteins associated with DR and/or DM; these were divided into those uniquely associated with diabetic retinopathy, uniquely associated with diabetes mellitus, and the ones seen in both conditions. The Gene Ontology PANTHER and STRING database analyses highlighted associations of several genes and proteins associated with diabetic retinopathy with adaptive immune response, valyl-TRNA aminoacylation, complement activation, and immune system processes. Our analyses highlight potential transcriptomic and proteomic biomarkers for DR and emphasize the association of known aspects of immune response, the complement system, advanced glycosylation end-product formation, and specific receptor and mitochondrial function with DR pathophysiology. These findings may suggest pathways for future research into novel diagnostic and therapeutic strategies for DR.
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Affiliation(s)
- Francesco Cappellani
- Wills Eye Hospital, Thomas Jefferson University, Philadelphia, PA 19107, USA; (F.C.)
- Department of Ophthalmology, University of Catania, 95123 Catania, Italy
| | - Carl D. Regillo
- Wills Eye Hospital, Thomas Jefferson University, Philadelphia, PA 19107, USA; (F.C.)
| | - Julia A. Haller
- Wills Eye Hospital, Thomas Jefferson University, Philadelphia, PA 19107, USA; (F.C.)
| | - Caterina Gagliano
- Faculty of Medicine and Surgery, University of Enna Kore, 94100 Enna, Italy;
- Ocular Immunology and Rare Diseases Unit, San Marco Hospital, 95123 Catania, Italy
| | - Jose S. Pulido
- Wills Eye Hospital, Thomas Jefferson University, Philadelphia, PA 19107, USA; (F.C.)
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Yang C, Yu Y, An J. Effect of High-Sucrose Diet on the Occurrence and Progression of Diabetic Retinopathy and Dietary Modification Strategies. Nutrients 2024; 16:1393. [PMID: 38732638 PMCID: PMC11085904 DOI: 10.3390/nu16091393] [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: 03/30/2024] [Revised: 04/29/2024] [Accepted: 05/02/2024] [Indexed: 05/13/2024] Open
Abstract
As the most serious of the many worse new pathological changes caused by diabetes, there are many risk factors for the occurrence and development of diabetic retinopathy (DR). They mainly include hyperglycemia, hypertension, hyperlipidemia and so on. Among them, hyperglycemia is the most critical cause, and plays a vital role in the pathological changes of DR. High-sucrose diets (HSDs) lead to elevated blood glucose levels in vivo, which, through oxidative stress, inflammation, the production of advanced glycation end products (AGEs) and vascular endothelial growth factor (VEGF), cause plenty of pathological damages to the retina and ultimately bring about loss of vision. The existing therapies for DR primarily target the terminal stage of the disease, when irreversible visual impairment has appeared. Therefore, early prevention is particularly critical. The early prevention of DR-related vision loss requires adjustments to dietary habits, mainly by reducing sugar intake. This article primarily discusses the risk factors, pathophysiological processes and molecular mechanisms associated with the development of DR caused by HSDs. It aims to raise awareness of the crucial role of diet in the occurrence and progression of DR, promote timely changes in dietary habits, prevent vision loss and improve the quality of life. The aim is to make people aware of the importance of diet in the occurrence and progression of DR. According to the dietary modification strategies that we give, patients can change their poor eating habits in a timely manner to avoid theoretically avoidable retinopathy and obtain an excellent prognosis.
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Affiliation(s)
- Chen Yang
- State Key Laboratory of Ophthalmology, Optometry and Vision Science, Wenzhou Medical University, Wenzhou 325027, China;
- Oujiang Laboratory, Zhejiang Lab for Regenerative Medicine, Vision and Brain Health, Wenzhou 325101, China
| | - Yifei Yu
- Key Laboratory of Precision Nutrition and Food Quality, Department of Nutrition and Health, China Agricultural University, Beijing 100193, China
| | - Jianhong An
- State Key Laboratory of Ophthalmology, Optometry and Vision Science, Wenzhou Medical University, Wenzhou 325027, China;
- Oujiang Laboratory, Zhejiang Lab for Regenerative Medicine, Vision and Brain Health, Wenzhou 325101, China
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Pan JY, Chen Y, Lin ZH, Lv B, Chen L, Feng SY. Association Between Triglyceride-Glucose Index and Hearing Threshold Shifts of Adults in the United States: National Health and Nutrition Examination Survey, 2015-2016. J Multidiscip Healthc 2024; 17:1791-1801. [PMID: 38686130 PMCID: PMC11056606 DOI: 10.2147/jmdh.s454678] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2024] [Accepted: 04/10/2024] [Indexed: 05/02/2024] Open
Abstract
Objective Sensorineural Hearing Loss (SNHL) is a representative human sensory impairment, few studies have paid attention to the correlation between the Triglyceride-Glucose (TyG) index and SNHL to date. We conducted this analysis to elucidate the correlation between the TyG index and pure tone hearing thresholds among US adults. Methods Our analysis included 1226 adults (age range: 20 to 69 years old) from the 2015-2016 National Health and Nutrition Examination Survey (NHANES) data. TyG index was scored into three quartiles. Weighted univariate analysis, weighted multivariate linear regression analyses as well as smooth curve fittings evaluated the associations between TyG index and pure tone hearing thresholds. Results In the multiple regression analysis, the second tertile of TyG index was negatively associated with high-frequency hearing thresholds shifts. Furthermore, the non-linear relationships between TyG index and speech-frequency and high-frequency hearing thresholds were identified by smooth curve fittings. After adjusting for potential confounders, the fitted smooth curves were approximately U-shaped, and the two-segment linear regression models were constructed to calculate their inflection points. Conclusion Our findings suggested that the TyG index was nearly U-shaped association with speech-frequency and high-frequency hearing thresholds. These results may imply the importance of maintaining a balanced TyG index in health management.
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Affiliation(s)
- Jia-Ying Pan
- Department of Otorhinolaryngology, Head and Neck Surgery, The Fifth Affiliated Hospital of Sun Yat-sen University, Zhuhai, Guangdong, People’s Republic of China
| | - Yuan Chen
- Department of Otorhinolaryngology, Head and Neck Surgery, The Fifth Affiliated Hospital of Sun Yat-sen University, Zhuhai, Guangdong, People’s Republic of China
| | - Zhi-He Lin
- Department of Otorhinolaryngology, Head and Neck Surgery, The Fifth Affiliated Hospital of Sun Yat-sen University, Zhuhai, Guangdong, People’s Republic of China
| | - Bo Lv
- Department of Otorhinolaryngology, Head and Neck Surgery, The Fifth Affiliated Hospital of Sun Yat-sen University, Zhuhai, Guangdong, People’s Republic of China
| | - Lei Chen
- Department of Neurosurgery, The Fifth Affiliated Hospital of Sun Yat-sen University, Zhuhai, Guangdong, People’s Republic of China
| | - Shao-Yan Feng
- Department of Otorhinolaryngology, Head and Neck Surgery, The Fifth Affiliated Hospital of Sun Yat-sen University, Zhuhai, Guangdong, People’s Republic of China
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Xia Y, Chen K, Yang Q, Chen Z, Jin L, Zhang L, Yu X, Wang L, Xie C, Zhao Y, Shen Y, Tong J. Methylation in cornea and corneal diseases: a systematic review. Cell Death Discov 2024; 10:169. [PMID: 38589350 PMCID: PMC11002037 DOI: 10.1038/s41420-024-01935-2] [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: 11/30/2023] [Revised: 03/24/2024] [Accepted: 03/25/2024] [Indexed: 04/10/2024] Open
Abstract
Corneal diseases are among the primary causes of blindness and vision loss worldwide. However, the pathogenesis of corneal diseases remains elusive, and diagnostic and therapeutic tools are limited. Thus, identifying new targets for the diagnosis and treatment of corneal diseases has gained great interest. Methylation, a type of epigenetic modification, modulates various cellular processes at both nucleic acid and protein levels. Growing evidence shows that methylation is a key regulator in the pathogenesis of corneal diseases, including inflammation, fibrosis, and neovascularization, making it an attractive potential therapeutic target. In this review, we discuss the major alterations of methylation and demethylation at the DNA, RNA, and protein levels in corneal diseases and how these dynamics contribute to the pathogenesis of corneal diseases. Also, we provide insights into identifying potential biomarkers of methylation that may improve the diagnosis and treatment of corneal diseases.
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Affiliation(s)
- Yutong Xia
- Department of Ophthalmology, The First Affiliated Hospital of Zhejiang University, Hangzhou, 310003, China
| | - Kuangqi Chen
- Department of Ophthalmology, The First Affiliated Hospital of Zhejiang University, Hangzhou, 310003, China
| | - Qianjie Yang
- Department of Ophthalmology, The First Affiliated Hospital of Zhejiang University, Hangzhou, 310003, China
| | - Zhitong Chen
- Department of Ophthalmology, The First Affiliated Hospital of Zhejiang University, Hangzhou, 310003, China
| | - Le Jin
- Department of Ophthalmology, The First Affiliated Hospital of Zhejiang University, Hangzhou, 310003, China
| | - Liyue Zhang
- Department of Ophthalmology, The First Affiliated Hospital of Zhejiang University, Hangzhou, 310003, China
| | - Xin Yu
- Department of Ophthalmology, The First Affiliated Hospital of Zhejiang University, Hangzhou, 310003, China
| | - Liyin Wang
- Department of Ophthalmology, The First Affiliated Hospital of Zhejiang University, Hangzhou, 310003, China
| | - Chen Xie
- Department of Ophthalmology, The First Affiliated Hospital of Zhejiang University, Hangzhou, 310003, China
| | - Yuan Zhao
- Department of Ophthalmology, The First Affiliated Hospital of Zhejiang University, Hangzhou, 310003, China
| | - Ye Shen
- Department of Ophthalmology, The First Affiliated Hospital of Zhejiang University, Hangzhou, 310003, China.
| | - Jianping Tong
- Department of Ophthalmology, The First Affiliated Hospital of Zhejiang University, Hangzhou, 310003, China.
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12
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Zhang C, Gu L, Xie H, Liu Y, Huang P, Zhang J, Luo D, Zhang J. Glucose transport, transporters and metabolism in diabetic retinopathy. Biochim Biophys Acta Mol Basis Dis 2024; 1870:166995. [PMID: 38142757 DOI: 10.1016/j.bbadis.2023.166995] [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: 08/02/2023] [Revised: 12/02/2023] [Accepted: 12/18/2023] [Indexed: 12/26/2023]
Abstract
Diabetic retinopathy (DR) is the most common reason for blindness in working-age individuals globally. Prolonged high blood glucose is a main causative factor for DR development, and glucose transport is prerequisite for the disturbances in DR caused by hyperglycemia. Glucose transport is mediated by its transporters, including the facilitated transporters (glucose transporter, GLUTs), the "active" glucose transporters (sodium-dependent glucose transporters, SGLTs), and the SLC50 family of uniporters (sugars will eventually be exported transporters, SWEETs). Glucose transport across the blood-retinal barrier (BRB) is crucial for nourishing the neuronal retina in the context of retinal physiology. This physiological process primarily relies on GLUTs and SGLTs, which mediate the glucose transportation across both the cell membrane of retinal capillary endothelial cells and the retinal pigment epithelium (RPE). Under diabetic conditions, increased accumulation of extracellular glucose enhances the retinal cellular glucose uptake and metabolism via both glycolysis and glycolytic side branches, which activates several biochemical pathways, including the protein kinase C (PKC), advanced glycation end-products (AGEs), polyol pathway and hexosamine biosynthetic pathway (HBP). These activated biochemical pathways further increase the production of reactive oxygen species (ROS), leading to oxidative stress and activation of Poly (ADP-ribose) polymerase (PARP). The activated PARP further affects all the cellular components in the retina, and finally resulting in microangiopathy, neurodegeneration and low-to-moderate grade inflammation in DR. This review aims to discuss the changes of glucose transport, glucose transporters, as well as its metabolism in DR, which influences the retinal neurovascular unit (NVU) and implies the possible therapeutic strategies for treating DR.
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Affiliation(s)
- Chaoyang Zhang
- Department of Ophthalmology, Shanghai General Hospital (Shanghai First People's Hospital), Shanghai Jiao Tong University School of Medicine, Shanghai, China; National Clinical Research Center for Eye Diseases; Shanghai Clinical Research Center for Eye Diseases; Shanghai Key Clinical Specialty; Shanghai Key Laboratory of Ocular Fundus Diseases; Shanghai Engineering Center for Visual Science and Photomedicine; Shanghai Engineering Center for Precise Diagnosis and Treatment of Eye Diseases, Shanghai Eye Research Institute, Shanghai, China.
| | - Limin Gu
- Department of Ophthalmology, Shanghai Aier Eye Hospital, Shanghai, China.
| | - Hai Xie
- Department of Ophthalmology, Shanghai General Hospital (Shanghai First People's Hospital), Shanghai Jiao Tong University School of Medicine, Shanghai, China; National Clinical Research Center for Eye Diseases; Shanghai Clinical Research Center for Eye Diseases; Shanghai Key Clinical Specialty; Shanghai Key Laboratory of Ocular Fundus Diseases; Shanghai Engineering Center for Visual Science and Photomedicine; Shanghai Engineering Center for Precise Diagnosis and Treatment of Eye Diseases, Shanghai Eye Research Institute, Shanghai, China.
| | - Yan Liu
- Department of Ophthalmology, Shanghai General Hospital (Shanghai First People's Hospital), Shanghai Jiao Tong University School of Medicine, Shanghai, China; National Clinical Research Center for Eye Diseases; Shanghai Clinical Research Center for Eye Diseases; Shanghai Key Clinical Specialty; Shanghai Key Laboratory of Ocular Fundus Diseases; Shanghai Engineering Center for Visual Science and Photomedicine; Shanghai Engineering Center for Precise Diagnosis and Treatment of Eye Diseases, Shanghai Eye Research Institute, Shanghai, China.
| | - Peirong Huang
- Department of Ophthalmology, Shanghai General Hospital (Shanghai First People's Hospital), Shanghai Jiao Tong University School of Medicine, Shanghai, China; National Clinical Research Center for Eye Diseases; Shanghai Clinical Research Center for Eye Diseases; Shanghai Key Clinical Specialty; Shanghai Key Laboratory of Ocular Fundus Diseases; Shanghai Engineering Center for Visual Science and Photomedicine; Shanghai Engineering Center for Precise Diagnosis and Treatment of Eye Diseases, Shanghai Eye Research Institute, Shanghai, China.
| | - Jingting Zhang
- Department of Ophthalmology, Shanghai General Hospital (Shanghai First People's Hospital), Shanghai Jiao Tong University School of Medicine, Shanghai, China; National Clinical Research Center for Eye Diseases; Shanghai Clinical Research Center for Eye Diseases; Shanghai Key Clinical Specialty; Shanghai Key Laboratory of Ocular Fundus Diseases; Shanghai Engineering Center for Visual Science and Photomedicine; Shanghai Engineering Center for Precise Diagnosis and Treatment of Eye Diseases, Shanghai Eye Research Institute, Shanghai, China.
| | - Dawei Luo
- Department of Ophthalmology, Shanghai General Hospital (Shanghai First People's Hospital), Shanghai Jiao Tong University School of Medicine, Shanghai, China; National Clinical Research Center for Eye Diseases; Shanghai Clinical Research Center for Eye Diseases; Shanghai Key Clinical Specialty; Shanghai Key Laboratory of Ocular Fundus Diseases; Shanghai Engineering Center for Visual Science and Photomedicine; Shanghai Engineering Center for Precise Diagnosis and Treatment of Eye Diseases, Shanghai Eye Research Institute, Shanghai, China.
| | - Jingfa Zhang
- Department of Ophthalmology, Shanghai General Hospital (Shanghai First People's Hospital), Shanghai Jiao Tong University School of Medicine, Shanghai, China; National Clinical Research Center for Eye Diseases; Shanghai Clinical Research Center for Eye Diseases; Shanghai Key Clinical Specialty; Shanghai Key Laboratory of Ocular Fundus Diseases; Shanghai Engineering Center for Visual Science and Photomedicine; Shanghai Engineering Center for Precise Diagnosis and Treatment of Eye Diseases, Shanghai Eye Research Institute, Shanghai, China.
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13
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Ding W, Yang X, Lai K, Jiang Y, Liu Y. The potential of therapeutic strategies targeting mitochondrial biogenesis for the treatment of insulin resistance and type 2 diabetes mellitus. Arch Pharm Res 2024; 47:219-248. [PMID: 38485900 DOI: 10.1007/s12272-024-01490-5] [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: 12/10/2023] [Accepted: 03/07/2024] [Indexed: 04/07/2024]
Abstract
Type 2 diabetes mellitus (T2DM) is a persistent metabolic disorder marked by deficiencies in insulin secretion and/or function, affecting various tissues and organs and leading to numerous complications. Mitochondrial biogenesis, the process by which cells generate new mitochondria utilizing existing ones plays a crucial role in energy homeostasis, glucose metabolism, and lipid handling. Recent evidence suggests that promoting mitochondrial biogenesis can alleviate insulin resistance in the liver, adipose tissue, and skeletal muscle while improving pancreatic β-cell function. Moreover, enhanced mitochondrial biogenesis has been shown to ameliorate T2DM symptoms and may contribute to therapeutic effects for the treatment of diabetic nephropathy, cardiomyopathy, retinopathy, and neuropathy. This review summarizes the intricate connection between mitochondrial biogenesis and T2DM, highlighting the potential of novel therapeutic strategies targeting mitochondrial biogenesis for T2DM treatment and its associated complications. It also discusses several natural products that exhibit beneficial effects on T2DM by promoting mitochondrial biogenesis.
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Affiliation(s)
- Wenwen Ding
- School of Life Sciences, Beijing University of Chinese Medicine, Beijing, 102488, China
| | - Xiaoxue Yang
- School of Life Sciences, Beijing University of Chinese Medicine, Beijing, 102488, China
| | - Kaiyi Lai
- School of Life Sciences, Beijing University of Chinese Medicine, Beijing, 102488, China
| | - Yu Jiang
- Department of Pharmacology and Chemical Biology, School of Medicine, University of Pittsburgh, Pittsburgh, PA, 15261, USA.
| | - Ying Liu
- School of Life Sciences, Beijing University of Chinese Medicine, Beijing, 102488, China.
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Luo Y, Li C. Advances in Research Related to MicroRNA for Diabetic Retinopathy. J Diabetes Res 2024; 2024:8520489. [PMID: 38375094 PMCID: PMC10876316 DOI: 10.1155/2024/8520489] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/31/2023] [Revised: 08/21/2023] [Accepted: 01/27/2024] [Indexed: 02/21/2024] Open
Abstract
Diabetic retinopathy (DR) is a severe microvascular complication of diabetes and is one of the primary causes of blindness in the working-age population in Europe and the United States. At present, no cure is available for DR, but early detection and timely intervention can prevent the rapid progression of the disease. Several treatments for DR are known, primarily ophthalmic treatment based on glycemia, blood pressure, and lipid control, which includes laser photocoagulation, glucocorticoids, vitrectomy, and antivascular endothelial growth factor (anti-VEGF) medications. Despite the clinical efficacy of the aforementioned therapies, none of them can entirely shorten the clinical course of DR or reverse retinopathy. MicroRNAs (miRNAs) are vital regulators of gene expression and participate in cell growth, differentiation, development, and apoptosis. MicroRNAs have been shown to play a significant role in DR, particularly in the molecular mechanisms of inflammation, oxidative stress, and neurodegeneration. The aim of this review is to systematically summarize the signaling pathways and molecular mechanisms of miRNAs involved in the occurrence and development of DR, mainly from the pathogenesis of oxidative stress, inflammation, and neovascularization. Meanwhile, this article also discusses the research progress and application of miRNA-specific therapies for DR.
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Affiliation(s)
- Yahan Luo
- Shanghai TCM-Integrated Hospital, Shanghai University of TCM, Shanghai, China
- Shanghai University of Traditional Chinese Medicine, Shanghai, China
| | - Chunxia Li
- Shanghai TCM-Integrated Hospital, Shanghai University of TCM, Shanghai, China
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15
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Zhong Y, Xia J, Liao L, Momeni MR. Non-coding RNAs and exosomal non-coding RNAs in diabetic retinopathy: A narrative review. Int J Biol Macromol 2024; 259:128182. [PMID: 37977468 DOI: 10.1016/j.ijbiomac.2023.128182] [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: 09/19/2023] [Revised: 11/06/2023] [Accepted: 11/14/2023] [Indexed: 11/19/2023]
Abstract
Diabetic retinopathy (DR) is a devastating complication of diabetes, having extensive and resilient effects on those who suffer from it. As yet, the underlying cell mechanisms of this microvascular disorder are largely unclear. Recently, growing evidence suggests that epigenetic mechanisms can be responsible for gene deregulation leading to the alteration of key processes in the development and progression of DR, in addition to the widely recognized pathological mechanisms. It is noteworthy that seemingly unending epigenetic modifications, caused by a prolonged period of hyperglycemia, may be a prominent factor that leads to metabolic memory, and brings epigenetic entities such as non-coding RNA into the equation. Consequently, further investigation is necessary to truly understand this mechanism. Exosomes are responsible for carrying signals from cells close to the vasculature that are participating in abnormal signal transduction to faraway organs and cells by sailing through the bloodstream. These signs indicate metabolic disorders. With the aid of their encased structure, they can store diverse signaling molecules, which then can be dispersed into the blood, urine, and tears. Herein, we summarized various non-coding RNAs (ncRNAs) that are related to DR pathogenesis. Moreover, we highlighted the role of exosomal ncRNAs in this disease.
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Affiliation(s)
- Yuhong Zhong
- Endocrinology Department, Sichuan Academy of Medical Sciences, Sichuan Provincial People's Hospital, Chengdu 610000, Sichuan, China
| | - Juan Xia
- Endocrinology Department, Sichuan Academy of Medical Sciences, Sichuan Provincial People's Hospital, Chengdu 610000, Sichuan, China
| | - Li Liao
- Department of Respiratory and Critical Care Medicine 3, Sichuan Academy of Medical Sciences Sichuan Provincial People's Hospital, Chengdu 610000, Sichuan, China.
| | - Mohammad Reza Momeni
- Institute for Immunology and Immune Health, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA, United States.
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Cubillos S, Kazlauskas A. Manifestation of Pathology in Animal Models of Diabetic Retinopathy Is Delayed from the Onset of Diabetes. Int J Mol Sci 2024; 25:1610. [PMID: 38338889 PMCID: PMC10855501 DOI: 10.3390/ijms25031610] [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: 12/18/2023] [Revised: 01/18/2024] [Accepted: 01/22/2024] [Indexed: 02/12/2024] Open
Abstract
Diabetic retinopathy (DR) is the most common complication that develops in patients with diabetes mellitus (DM) and is the leading cause of blindness worldwide. Fortunately, sight-threatening forms of DR develop only after several decades of DM. This well-documented resilience to DR suggests that the retina is capable of protecting itself from DM-related damage and also that accumulation of such damage occurs only after deterioration of this resilience. Despite the enormous translational significance of this phenomenon, very little is known regarding the nature of resilience to DR. Rodent models of DR have been used extensively to study the nature of the DM-induced damage, i.e., cardinal features of DR. Many of these same animal models can be used to investigate resilience because DR is delayed from the onset of DM by several weeks or months. The purpose of this review is to provide a comprehensive overview of the literature describing the use of rodent models of DR in type-1 and type-2 diabetic animals, which most clearly document the delay between the onset of DM and the appearance of DR. These readily available experimental settings can be used to advance our current understanding of resilience to DR and thereby identify biomarkers and targets for novel, prevention-based approaches to manage patients at risk for developing DR.
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Affiliation(s)
- Samuel Cubillos
- University of Illinois at Chicago, College of Medicine, Chicago, IL 60612, USA;
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Malaviya P, Kowluru RA. Homocysteine and mitochondrial quality control in diabetic retinopathy. EYE AND VISION (LONDON, ENGLAND) 2024; 11:5. [PMID: 38229140 PMCID: PMC10790378 DOI: 10.1186/s40662-023-00362-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/21/2023] [Accepted: 10/08/2023] [Indexed: 01/18/2024]
Abstract
BACKGROUND Diabetic retinopathy is a progressive disease, and one of the key metabolic abnormalities in the pathogenesis of diabetic retinopathy, mitochondrial damage, is also influenced by the duration of hyperglycemia. Mitochondrial quality control involves a coordination of mitochondrial dynamics, biogenesis and removal of the damaged mitochondria. In diabetes, these processes are impaired, and the damaged mitochondria continue to produce free radicals. Diabetic patients also have high homocysteine and reduced levels of hydrogen sulfide, and hyperhomocysteinemia is shown to exacerbate diabetes-induced mitochondrial damage and worsen their dynamics. This study aims to investigate the temporal relationship between hyperhomocysteinemia and retinal mitochondrial quality control in diabetic retinopathy. METHODS Human retinal endothelial cells incubated in 20 mM D-glucose for 24 to 96 h, in the absence or presence of 100 µM homocysteine, with/without a hydrogen sulfide donor GYY4137, were analyzed for mitochondrial ROS (MitoSox fluorescence), DNA damage (transcripts of mtDNA-encoded ND6 and CytB), copy numbers, oxygen consumption rate (Seahorse XF analyzer) and mitophagy (mitophagosomes immunofluorescence labeling and flow cytometry). Results were confirmed in the retina from mice genetically manipulated for hyperhomocysteinemia (cystathionine β-synthase deficient mice, Cbs+/-), streptozotocin-induced diabetic for 8 to 24 weeks. At 24 weeks of diabetes, vascular health was evaluated by counting acellular capillaries in the trypsin digested retinal vasculature and by fluorescein angiography. RESULTS Homocysteine, in high glucose medium, exacerbated mitochondrial ROS production, mtDNA damage and impaired mitochondrial respiration within 24 h, and slowed down/worsened mitochondrial biogenesis and mitophagy, as compared to 48 to 96 h in high glucose alone. GYY4137 supplementation ameliorated homocysteine + high glucose-induced mitochondrial damage and impairment in biogenesis and mitophagy. Similar results were obtained from Cbs+/- mice-mitochondrial ROS, mtDNA damage and decline in biogenesis and mitophagy were observed within eight weeks of diabetes vs. 16 to 24 weeks of diabetes in Cbs+/+ mice, and at 24 weeks of diabetes, Cbs+/- mice had significantly higher acellular capillaries and vascular leakage. CONCLUSIONS Hyperhomocysteinemia, in a hyperglycemic environment, overwhelms the mitochondria, accelerating and exacerbating their dysfunction, and also delays/worsens their removal, augmenting the development of diabetic retinopathy. Thus, our results strengthen the importance of maintaining homocysteine-hydrogen sulfide balance during the early stages of diabetes for a patient to prevent/retard vision loss.
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Affiliation(s)
- Pooja Malaviya
- Department of Ophthalmology, Visual Sciences and Anatomical Sciences, Wayne State University, 4717 St. Antoine, Detroit, MI, 48201, USA
| | - Renu A Kowluru
- Department of Ophthalmology, Visual Sciences and Anatomical Sciences, Wayne State University, 4717 St. Antoine, Detroit, MI, 48201, USA.
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Li S, Sun D, Chen S, Zhang S, Gu Q, Shen Y, Xu L, Xu X, Wei F, Wang N. UCP2-SIRT3 Signaling Relieved Hyperglycemia-Induced Oxidative Stress and Senescence in Diabetic Retinopathy. Invest Ophthalmol Vis Sci 2024; 65:14. [PMID: 38175638 PMCID: PMC10774691 DOI: 10.1167/iovs.65.1.14] [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: 05/04/2023] [Accepted: 11/09/2023] [Indexed: 01/05/2024] Open
Abstract
Purpose Diabetic retinopathy (DR) is one of the most common reasons for blindness. uncoupling protein 2 (UCP2), an uncoupling protein located in mitochondria, has been reported to be related to metabolic and vascular diseases. This research aimed to illustrate the function and mechanism of UCP2 in the pathogenesis of DR. Methods Human epiretinal membranes were collected to investigate the expression of UCP2 by quantitative real-time polymerase chain reaction (qRT-PCR) and immunofluorescence. Primary human retinal microvascular endothelial cells (HRECs) were cultured in high glucose (HG) to establish an in vitro cell model for DR. Flow cytometry analysis was used to measure intracellular reactive oxygen species (ROS). Senescence levels were evaluated by the senescence-associated beta-galactosidase (SA-β-gal) assay, the expression of senescence marker P21, and cell-cycle analysis. Adenovirus-mediated UCP2 overexpression or knockdown and specific inhibitors were administered to investigate the underlying regulatory mechanism. Results Proliferative fibrovascular membranes from patients with DR illustrated the downregulation of UCP2 and sirtuin 3 (SIRT3) by qRT-PCR and immunofluorescence. Persistent hyperglycemia-induced UCP2 downregulation in the progress of DR and adenovirus-mediated UCP2 overexpression protected endothelial cells from hyperglycemia-induced oxidative stress and senescence. Under hyperglycemic conditions, UCP2 overexpression attenuated NAD+ downregulation; hence, it promoted the expression and activity of SIRT3, an NAD+-dependent deacetylase regulating mitochondrial function. 3-TYP, a selective SIRT3 inhibitor, abolished the UCP2-mediated protective effect against oxidative stress and senescence. Conclusions UCP2 overexpression relieved oxidative stress and senescence based on a novel mechanism whereby UCP2 can regulate the NAD+-SIRT3 axis. Targeting oxidative stress and senescence amelioration, UCP2-SIRT3 signaling may serve as a method for the prevention and treatment of DR and other diabetic vascular diseases.
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Affiliation(s)
- Shenping Li
- Department of Ophthalmology, Shanghai General Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
- Department of Ophthalmology, Shanghai General Hospital, Shanghai, China
| | - Dandan Sun
- Department of Ophthalmology, Shanghai General Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
- Department of Ophthalmology, Shanghai General Hospital, Shanghai, China
| | - Shimei Chen
- Department of Ophthalmology, Shanghai General Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
- Department of Ophthalmology, Shanghai General Hospital, Shanghai, China
| | - Shuchang Zhang
- Department of Ophthalmology, Shanghai General Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
- Department of Ophthalmology, Shanghai General Hospital, Shanghai, China
| | - Qing Gu
- Department of Ophthalmology, Shanghai General Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
- National Clinical Research Center for Eye Diseases, Shanghai, China
- Shanghai Key Laboratory of Ocular Fundus Diseases, Shanghai, China
| | - Yinchen Shen
- Department of Ophthalmology, Shanghai General Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
- Department of Ophthalmology, Shanghai General Hospital, Shanghai, China
- National Clinical Research Center for Eye Diseases, Shanghai, China
| | - Li Xu
- Department of Ophthalmology, Shanghai General Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
- Department of Ophthalmology, Shanghai General Hospital, Shanghai, China
| | - Xun Xu
- Department of Ophthalmology, Shanghai General Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
- Department of Ophthalmology, Shanghai General Hospital, Shanghai, China
- National Clinical Research Center for Eye Diseases, Shanghai, China
- Shanghai Key Laboratory of Ocular Fundus Diseases, Shanghai, China
- Shanghai Engineering Center for Visual Science and Photomedicine, Shanghai, China
| | - Fang Wei
- Department of Ophthalmology, Shanghai General Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
- Department of Ophthalmology, Shanghai General Hospital, Shanghai, China
- National Clinical Research Center for Eye Diseases, Shanghai, China
- Shanghai Key Laboratory of Ocular Fundus Diseases, Shanghai, China
- Shanghai Engineering Center for Visual Science and Photomedicine, Shanghai, China
| | - Ning Wang
- Department of Ophthalmology, Shanghai General Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
- Department of Ophthalmology, Shanghai General Hospital, Shanghai, China
- National Clinical Research Center for Eye Diseases, Shanghai, China
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Tai LA, Tsai LY, Lin CH, Chiu YC. Depressive symptoms and daily living dependence in older adults with type 2 diabetes mellitus: the mediating role of positive and negative perceived stress. BMC Psychiatry 2024; 24:14. [PMID: 38166717 PMCID: PMC10762910 DOI: 10.1186/s12888-023-05273-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/19/2023] [Accepted: 10/11/2023] [Indexed: 01/05/2024] Open
Abstract
BACKGROUND Higher stress is associated with higher levels of depression and instrumental-activities-of-daily-living (IADL) dependence, and depression is strongly associated with specific IADL disabilities. Accordingly, the aim of this study was to investigate the mediating effect of perceived stress on the association between depression and IADL dependence among older adults with diabetes mellitus (DM). METHODS We examined baseline data collected from a longitudinal study that recruited 110 patients with DM aged ≥ 65 years from the endocrinology outpatient clinic of a district hospital. The instruments used for our measurement processes comprised a demographic data sheet and Chinese versions of the Perceived Stress Scale (PSS), the short form of the Geriatric Depression Scale (GDS-S), and the Lawton IADL Scale. We assessed the mediating effects of positive perceived stress (PPS) and negative perceived stress (NPS) after controlling for five covariates by using a regression-based model run through the SPSS macro PROCESS. RESULTS We observed negative correlations between GDS-S scores and PPS and between PPS and IADL dependence; we noted positive correlations between GDS-S scores and NPS and between NPS and IADL dependence (all P < 0.01). The indirect effect is coefficient = 0.12, [95% confidence interval = (0.0, 0.33)], suggesting that PPS achieves a mediating effect between depressive symptoms and IADL dependence. However, the NPS does not achieve a mediating effect in the relationship between depressive symptoms and IADL dependence (coefficient = 0.06, 95% CI = - 0.03, 0.15). CONCLUSIONS Personal PPS mediates the association between depression and IADL dependence in older adults with DM. This finding suggests that providing patients with psychological education to promote their PPS may help prevent their functional decline.
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Affiliation(s)
- Li Ai Tai
- Graduate Institute of Clinical Medical Science, College of Medicine, Chang Gung University, Taoyuan, Taiwan
- Department of Nursing, Cardinal Tien Junior College of Healthcare and Management, New Taipei, Taiwan
| | - Le Yu Tsai
- Department of Endocrinology and Metabolism, Yonghe Cardinal Tien Hospital, New Taipei, Taiwan
| | - Chia Hung Lin
- Division of Endocrinology and Metabolism, Department of Internal Medicine, Chang Gung Memorial Hospital, Linkou, Taoyuan, Taiwan
- College of Medicine, Chang Gung University, Taoyuan, Taiwan
| | - Yi Chen Chiu
- School of Nursing, College of Medicine, Chang Gung University, Taoyuan, Taiwan.
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Kour V, Swain J, Singh J, Singh H, Kour H. A Review on Diabetic Retinopathy. Curr Diabetes Rev 2024; 20:e201023222418. [PMID: 37867267 DOI: 10.2174/0115733998253672231011161400] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/24/2023] [Revised: 07/08/2023] [Accepted: 08/23/2023] [Indexed: 10/24/2023]
Abstract
Diabetic retinopathy is a well-recognised microvascular complication of diabetes and is among the leading cause of blindness all over the world. Over the last decade, there have been advances in the diagnosis of diabetic retinopathy and diabetic macular edema. At the same time, newer therapies for the management of diabetic retinopathy have evolved. As a result of these advances, a decline in severe vision loss due to diabetes has been witnessed in some developing countries. However, there is a steady increase in the number of people affected with diabetes, and is expected to rise further in the coming years. Therefore, it is prudent to identify diabetic retinopathy, and timely intervention is needed to decrease the burden of severe vision loss. An effort has been made to review all the existing knowledge regarding diabetic retinopathy in this article and summarize the present treatment options for diabetic retinopathy.
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Affiliation(s)
- Vijender Kour
- Consultant Ophthalmology, Department of Ophthalmology, Sub District Hospital, Tral, Pulwama, India
| | - Jayshree Swain
- Department of Endocrinology, IMS and Sum Hospital, Siksha O Anusandhan (SOA) University, Bhubaneswar, India
| | - Jaspreet Singh
- Department of Endocrinology, IMS and Sum Hospital, Siksha O Anusandhan (SOA) University, Bhubaneswar, India
| | - Hershdeep Singh
- Consultant Neurosurgeon, Department of Neurosurgery, Fortis Ludhiana, Bhubaneswar, India
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Biswas A, Choudhury AD, Agrawal S, Bisen AC, Sanap SN, Verma SK, Kumar M, Mishra A, Kumar S, Chauhan M, Bhatta RS. Recent Insights into the Etiopathogenesis of Diabetic Retinopathy and Its Management. J Ocul Pharmacol Ther 2024; 40:13-33. [PMID: 37733327 DOI: 10.1089/jop.2023.0068] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 09/22/2023] Open
Abstract
Purpose: Diabetic retinopathy (DR) is a microvascular retinal disease associated with chronic diabetes mellitus, characterized by the damage of blood vessels in the eye. It is projected to become the leading cause of blindness, given the increasing burden of the diabetic population worldwide. The diagnosis and management of DR pose significant challenges for physicians because of the involvement of multiple biochemical pathways and the complexity of ocular tissues. This review aims to provide a comprehensive understanding of the molecular pathways implicated in the pathogenesis of DR, including the polyo pathway, hexosamine pathway, protein kinase C (PKC), JAK/STAT signaling pathways, and the renin-angiotensin system (RAS). Methods: Academic databases such as PubMed, Scopus, Google Scholar and Web of Science was systematically searched using a carefully constructed search strategy incorporating keywords like "Diabetic Retinopathy," "Molecular Pathways," "Pharmacological Treatments," and "Clinical Trials" to identify relevant literature for the comprehensive review. Results: In addition to activating other inflammatory cascades, these pathways contribute to the generation of oxidative stress within the retina. Furthermore, it aims to explore the existing pharmacotherapy options available for the treatment of DR. In addition to conventional pharmacological therapies such as corticosteroids, antivascular endothelial growth factors, and nonsteroidal anti-inflammatory drugs (NSAIDs), this review highlights the potential of repurposed drugs, phyto-pharmaceuticals, and novel pipeline drugs currently undergoing various stages of clinical trials. Conclusion: Overall, this review serves as a technical exploration of the complex nature of DR, highlighting both established and emerging molecular pathways implicated in its pathogenesis. Furthermore, it delves into the available pharmacological treatments, as well as the promising repurposed drugs, phyto-pharmaceuticals, and novel drugs currently being evaluated in clinical trials, with a focus on their specific mechanisms of action.
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Affiliation(s)
- Arpon Biswas
- Pharmaceutics and Pharmacokinetic Division, CSIR-Central Drug Research Institute, Lucknow, India
- Jawaharlal Nehru University, New Delhi, India
| | - Abhijit Deb Choudhury
- Pharmaceutics and Pharmacokinetic Division, CSIR-Central Drug Research Institute, Lucknow, India
- Jawaharlal Nehru University, New Delhi, India
| | - Sristi Agrawal
- Pharmaceutics and Pharmacokinetic Division, CSIR-Central Drug Research Institute, Lucknow, India
- Academy of Scientific and Innovative Research, New Delhi, India
| | - Amol Chhatrapati Bisen
- Pharmaceutics and Pharmacokinetic Division, CSIR-Central Drug Research Institute, Lucknow, India
- Academy of Scientific and Innovative Research, New Delhi, India
| | - Sachin Nashik Sanap
- Pharmaceutics and Pharmacokinetic Division, CSIR-Central Drug Research Institute, Lucknow, India
- Academy of Scientific and Innovative Research, New Delhi, India
| | - Sarvesh Kumar Verma
- Pharmaceutics and Pharmacokinetic Division, CSIR-Central Drug Research Institute, Lucknow, India
- Jawaharlal Nehru University, New Delhi, India
| | - Mukesh Kumar
- Pharmaceutics and Pharmacokinetic Division, CSIR-Central Drug Research Institute, Lucknow, India
- Jawaharlal Nehru University, New Delhi, India
| | - Anjali Mishra
- Pharmaceutics and Pharmacokinetic Division, CSIR-Central Drug Research Institute, Lucknow, India
- Academy of Scientific and Innovative Research, New Delhi, India
| | - Shivansh Kumar
- Pharmaceutics and Pharmacokinetic Division, CSIR-Central Drug Research Institute, Lucknow, India
| | - Mridula Chauhan
- Pharmaceutics and Pharmacokinetic Division, CSIR-Central Drug Research Institute, Lucknow, India
| | - Rabi Sankar Bhatta
- Pharmaceutics and Pharmacokinetic Division, CSIR-Central Drug Research Institute, Lucknow, India
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22
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Kowluru RA, Mohammad G, Kumar J. Impaired Removal of the Damaged Mitochondria in the Metabolic Memory Phenomenon Associated with Continued Progression of Diabetic Retinopathy. Mol Neurobiol 2024; 61:188-199. [PMID: 37596436 PMCID: PMC10791911 DOI: 10.1007/s12035-023-03534-1] [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: 12/23/2022] [Accepted: 07/21/2023] [Indexed: 08/20/2023]
Abstract
Retinopathy fails to halt even after diabetic patients in poor glycemic control try to institute tight glycemic control, suggesting a "metabolic memory" phenomenon, and the experimental models have demonstrated that mitochondria continue to be damaged/dysfunctional, fueling into the vicious cycle of free radicals. Our aim was to investigate the role of removal of the damaged mitochondria in the metabolic memory. Using human retinal endothelial cells (HRECs), incubated in 20 mM D-glucose for 4 days, followed by 5 mM D-glucose for 4 additional days, mitochondrial turnover, formation of mitophagosome, and mitophagy flux were evaluated. Mitophagy was confirmed in a rat model of metabolic memory where the rats were kept in poor glycemic control (blood glucose ~ 400 mg/dl) for 3 months soon after induction of streptozotocin-induced diabetes, followed by 3 additional months of good control (BG < 150 mg/dl). Reversal of high glucose by normal glucose had no effect on mitochondrial turnover and mitophagosome formation, and mitophagy flux remained compromised. Similarly, 3 months of good glycemic control in rats, which had followed 3 months of poor glycemic control, had no effect on mitophagy flux. Thus, poor turnover/removal of the damaged mitochondria, initiated during poor glycemic control, does not benefit from the termination of hyperglycemic insult, and the damaged mitochondria continue to produce free radicals, suggesting the importance of mitophagy in the metabolic memory phenomenon associated with the continued progression of diabetic retinopathy.
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Affiliation(s)
- Renu A Kowluru
- Ophthalmology, Visual and Anatomical Sciences, Wayne State University, Detroit, MI, USA.
| | - Ghulam Mohammad
- Ophthalmology, Visual and Anatomical Sciences, Wayne State University, Detroit, MI, USA
| | - Jay Kumar
- Ophthalmology, Visual and Anatomical Sciences, Wayne State University, Detroit, MI, USA
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23
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Yu W, Yang B, Xu S, Gao Y, Huang Y, Wang Z. Diabetic Retinopathy and Cardiovascular Disease: A Literature Review. Diabetes Metab Syndr Obes 2023; 16:4247-4261. [PMID: 38164419 PMCID: PMC10758178 DOI: 10.2147/dmso.s438111] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/01/2023] [Accepted: 12/21/2023] [Indexed: 01/03/2024] Open
Abstract
Diabetic complications can be divided into macrovascular complications such as cardiovascular disease and cerebrovascular disease and microvascular complications such as diabetic retinopathy, diabetic nephropathy and diabetic neuropathy. Among them, cardiovascular disease (CVD) is an important cause of death in diabetic patients. Diabetes retinopathy (DR) is one of the main reasons for the increasing disability rate of diabetes. In recent years, some studies have found that because DR and CVD have a common pathophysiological basis, the occurrence of DR and CVD are inseparable, and to a certain extent, DR can predict the occurrence of CVD. With the development of technology, the fundus parameters of DR can be quantitatively analyzed as an independent risk factor of CVD. In addition, the cytokines related to DR can also be used for early screening of DR. Although many advances have been made in the treatment of CVD, its situation of prevention and treatment is still not optimistic. This review hopes to discuss the feasibility of DR in predicting CVD from the common pathophysiological mechanism of DR and CVD, the new progress of diagnostic techniques for DR, and the biomarkers for early screening of DR.
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Affiliation(s)
- Wenhua Yu
- Department of Cardiology, Affiliated Hospital of Jiangsu University, Zhenjiang, People’s Republic of China
| | - Bo Yang
- Department of Cardiology, Affiliated Hospital of Jiangsu University, Zhenjiang, People’s Republic of China
| | - Siting Xu
- Department of Cardiology, Affiliated Hospital of Jiangsu University, Zhenjiang, People’s Republic of China
| | - Yun Gao
- Department of Pathology, Affiliated Hospital of Jiangsu University, Zhenjiang, People’s Republic of China
| | - Yan Huang
- Department of Ophthalmology, Affiliated Hospital of Jiangsu University, Zhenjiang, People’s Republic of China
| | - Zhongqun Wang
- Department of Cardiology, Affiliated Hospital of Jiangsu University, Zhenjiang, People’s Republic of China
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24
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Mohammad G, Kumar J, Kowluru RA. Mitochondrial Genome-Encoded Long Noncoding RNA Cytochrome B and Mitochondrial Dysfunction in Diabetic Retinopathy. Antioxid Redox Signal 2023; 39:817-828. [PMID: 37464864 PMCID: PMC10654995 DOI: 10.1089/ars.2023.0303] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/14/2023] [Accepted: 06/22/2023] [Indexed: 07/20/2023]
Abstract
Aims: Mitochondrial dysfunction is closely associated with the development of diabetic complications. In diabetic retinopathy, electron transport chain is compromised and mitochondrial DNA (mtDNA) is damaged, downregulating transcription of mtDNA-encoded cytochrome B (CYTB) and its antisense long noncoding RNA, long noncoding RNA cytochrome B (LncCytB). Our goal was to investigate the role of LncCytB in the regulation of CYTB and mitochondrial function in diabetic retinopathy. Methods: Using human retinal endothelial cells, genetically manipulated for LncCytB (overexpression or silencing), the effect of high glucose (20 mM d-glucose) on LncCytB-CYTB interactions (by chromatin isolation by RNA purification), CYTB gene expression (by real-time quantitative polymerase chain reaction), complex III activity, mitochondrial free radicals, and oxygen consumption rate (OCR, by Seahorse XF analyzer) was investigated. Key results were confirmed in the retinal microvessels from streptozotocin-induced diabetic mice. Results: High glucose decreased LncCytB-CYTB interactions, and while LncCytB overexpression ameliorated glucose-induced decrease in CYTB gene transcripts, complex III activity and OCR and increase in mitochondrial reactive oxygen species, LncCytB-siRNA further attenuated CYTB gene transcription, complex III activity, and OCR. Similar decrease in LncCytB-CYTB interactions and CYTB transcription was observed in diabetic mice. Furthermore, maintenance of mitochondrial homeostasis by overexpressing superoxide dismutase or sirtuin 1 in mice ameliorated diabetes-induced decrease in LncCytB-CYTB interactions and CYTB gene transcripts, and also improved complex III activity and mitochondrial respiration. Innovation and Conclusion: LncCytB downregulation in hyperglycemic milieu downregulates CYTB transcription, which inhibits complex III activity and compromises mitochondrial stability and OCR. Thus, preventing LncCytB downregulation in diabetes has potential of inhibiting the development of diabetic retinopathy, possibly via maintaining mitochondrial respiration. Antioxid. Redox Signal. 39, 817-828.
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Affiliation(s)
- Ghulam Mohammad
- Department of Ophthalmology, Visual and Anatomical Sciences, Wayne State University, Detroit, Michigan, USA
| | - Jay Kumar
- Department of Ophthalmology, Visual and Anatomical Sciences, Wayne State University, Detroit, Michigan, USA
| | - Renu A. Kowluru
- Department of Ophthalmology, Visual and Anatomical Sciences, Wayne State University, Detroit, Michigan, USA
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25
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Suciu CI, Suciu VI, Nicoară SD. Optical Coherence Tomography Measurements in Type 1 Diabetic Subjects with Low and Moderate Daily Physical Activity. Rom J Ophthalmol 2023; 67:337-344. [PMID: 38239425 PMCID: PMC10793371 DOI: 10.22336/rjo.2023.54] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 11/21/2023] [Indexed: 01/22/2024] Open
Abstract
Background: Physical activity is nowadays recognized as a protective factor against cardiovascular conditions, being cost-effective and easy to implement. Through its positive effects on hemodynamic and oxidative stress, different intensities in daily physical activity could influence diabetic macular edema (DME) in type 1 Diabetes Mellitus (DM). Methods: With the help of a spectral domain optical coherence tomography (OCT) device, we studied the macular thickness and ETDRS map parameters in type 1 DM patients who were classified into two groups: low and moderate intensity routine physical activity status, using the international physical activity questionnaire (IPAQ). All subjects received comparable anti-VEGF treatment. Results: Having a long disease evolution, patients with type 1 DM (T1DM) with moderate physical activity displayed better OCT measurements in specific retinal sectors than their counterparts with low physical activity. Variables such as age and body mass index (BMI) can influence the level of physical activity in T1DM patients. Conclusions: This study showed a lower prevalence of DME in T1DM subjects with moderate physical activity levels, revealing lower values for ETDRS OCT parameters in specific retinal sectors. The macular volumes (mm3) were significantly lower in the right eye for this group of subjects. Abbreviations: BMI = body mass index, CMT = central macular thickness, DM = diabetes mellitus, DME = diabetic macular edema, DR = diabetic retinopathy, FT = foveal thickness, II = inferior inner thickness, IO = inferior outer thickness, IPAQ = international physical activity questionnaire, LE = left eye, OCT = optical coherence tomography, MMT = maximal macular thickness, mMT = minimal macular thickness, MV = macular volume, NI = nasal inner thickness, NO = nasal outer thickness, QoL = quality of life, RE = right eye, SI = superior inner thickness, SO = superior outer thickness, T1DM = type 1 diabetes mellitus, T2DM = type 2 diabetes mellitus, TI = temporal inner thickness, TO = temporal outer thickness.
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Affiliation(s)
- Corina-Iuliana Suciu
- Department of Ophthalmology, "Iuliu Haţieganu" University of Medicine and Pharmacy, Cluj-Napoca, Romania
| | - Vlad-Ioan Suciu
- Department of Neuroscience, "Iuliu Haţieganu" University of Medicine and Pharmacy, Cluj-Napoca, Romania
| | - Simona Delia Nicoară
- Department of Ophthalmology, "Iuliu Haţieganu" University of Medicine and Pharmacy, Cluj-Napoca, Romania
- Department of Ophthalmology, Emergency County Hospital, Cluj-Napoca, Romania
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26
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Yao Y, Li J, Zhou Y, Wang S, Zhang Z, Jiang Q, Li K. Macrophage/microglia polarization for the treatment of diabetic retinopathy. Front Endocrinol (Lausanne) 2023; 14:1276225. [PMID: 37842315 PMCID: PMC10569308 DOI: 10.3389/fendo.2023.1276225] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/11/2023] [Accepted: 09/07/2023] [Indexed: 10/17/2023] Open
Abstract
Macrophages/microglia are immune system defense and homeostatic cells that develop from bone marrow progenitor cells. According to the different phenotypes and immune responses of macrophages (Th1 and Th2), the two primary categories of polarized macrophages/microglia are those conventionally activated (M1) and alternatively activated (M2). Macrophage/microglial polarization is a key regulating factor in the development of inflammatory disorders, cancers, metabolic disturbances, and neural degeneration. Macrophage/microglial polarization is involved in inflammation, oxidative stress, pathological angiogenesis, and tissue healing processes in ocular diseases, particularly in diabetic retinopathy (DR). The functional phenotypes of macrophages/microglia affect disease progression and prognosis, and thus regulate the polarization or functional phenotype of microglia at different DR stages, which may offer new concepts for individualized therapy of DR. This review summarizes the involvement of macrophage/microglia polarization in physiological situations and in the pathological process of DR, and discusses the promising role of polarization in personalized treatment of DR.
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Affiliation(s)
- Yujia Yao
- Department of Ophthalmology, The Affiliated Eye Hospital of Nanjing Medical University, Nanjing, China
- The Fourth School of Clinical Medicine, Nanjing Medical University, Nanjing, China
| | - Jiajun Li
- Department of Ophthalmology, The Affiliated Eye Hospital of Nanjing Medical University, Nanjing, China
- The Fourth School of Clinical Medicine, Nanjing Medical University, Nanjing, China
| | - Yunfan Zhou
- Department of Ophthalmology, The Affiliated Eye Hospital of Nanjing Medical University, Nanjing, China
- The Fourth School of Clinical Medicine, Nanjing Medical University, Nanjing, China
| | - Suyu Wang
- Department of Ophthalmology, The Affiliated Eye Hospital of Nanjing Medical University, Nanjing, China
- The Fourth School of Clinical Medicine, Nanjing Medical University, Nanjing, China
| | - Ziran Zhang
- Department of Ophthalmology, The Affiliated Eye Hospital of Nanjing Medical University, Nanjing, China
- The Fourth School of Clinical Medicine, Nanjing Medical University, Nanjing, China
| | - Qin Jiang
- Department of Ophthalmology, The Affiliated Eye Hospital of Nanjing Medical University, Nanjing, China
- The Fourth School of Clinical Medicine, Nanjing Medical University, Nanjing, China
| | - Keran Li
- Department of Ophthalmology, The Affiliated Eye Hospital of Nanjing Medical University, Nanjing, China
- The Fourth School of Clinical Medicine, Nanjing Medical University, Nanjing, China
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27
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Banasaz B, Zamzam R, Aghadoost D, Golabchi K, Morshedi M, Bayat M, Sadri Nahand J, Sheida A, Eshraghi R, Rahimzadeh Z, Mosavi SG, Goleij P, Rezaee A, Mirzaei H. Evaluation of expression pattern of cellular miRNAs (let-7b, miR-29a, miR-126, miR-34a, miR-181a-5p) and IL-6, TNF-α, and TGF-β in patients with pseudoexfoliation syndrome. Pathol Res Pract 2023; 249:154721. [PMID: 37591069 DOI: 10.1016/j.prp.2023.154721] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/25/2023] [Revised: 07/20/2023] [Accepted: 07/26/2023] [Indexed: 08/19/2023]
Abstract
Pseudoexfoliation syndrome (PEX) is a critical clinical and biological extracellular matrix systemic disorder. Despite the unknown nature of PEX etiopathogenesis, it is proven to be associated with various genes and factors. The present research focused on analyzing the expression of miR and inflammatory cytokines in PEX. Serum and aqueous humor (AH) were collected prior to cataract surgery or trabeculectomy from 99 participants (64 with PEX glaucoma, and 35 controls). Real-time PCR was used for assessing the expression pattern of some miRNAs namely let-7b, miR-29a, miR-126, miR-34a, and miR-181a-5p. ELISA was carried out to explore the transcription of some inflammatory cytokines such as TGF-β, TNF-α, and IL-6. The indication of our results was a significant enhancement in the expression of let-7, miR-34a, and miR-181a-5p in PEX in contrast to the control group. Notwithstanding a significant suppression in miR-29a, and miR-126 expression levels in PEX in contrast to the control group. Analysis of ROC curve revealed that miR-29a and miR-34a are able to act as useful markers in order to discriminate the PEX group from the PEX negative subjects which were determined as the control group. According to the results obtained, the mean levels of TGF-β, TNF-α, and IL-6 upregulated among PEX subjects in contrast to control samples. In conclusion, our findings indicated that the selected cytokines alongside the selected miRNAs could be introduced as a biomarker panel in the diagnosis of PEX.
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Affiliation(s)
- Bahar Banasaz
- Internal Medicine Department, Babol University of Medical Sciences, Babol, Islamic Republic of Iran
| | - Razieh Zamzam
- School of Medicine, Kashan University of Medical Sciences, Kashan, Islamic Republic of Iran
| | - Davood Aghadoost
- Department of Ophthalmology, General Ophthalmologist, Matini Hospital, Kashan University of Medical Sciences, Kashan, Islamic Republic of Iran
| | - Khodayar Golabchi
- Department of Ophthalmology, General Ophthalmologist, Matini Hospital, Kashan University of Medical Sciences, Kashan, Islamic Republic of Iran
| | - Mohammadamin Morshedi
- School of Medicine, Kashan University of Medical Sciences, Kashan, Islamic Republic of Iran
| | - Mobina Bayat
- Infectious and Tropical Diseases Research Center, Tabriz University of Medical Sciences, Tabriz, Islamic Republic of Iran
| | - Javid Sadri Nahand
- Infectious and Tropical Diseases Research Center, Tabriz University of Medical Sciences, Tabriz, Islamic Republic of Iran
| | - Amirhossein Sheida
- School of Medicine, Kashan University of Medical Sciences, Kashan, Islamic Republic of Iran
| | - Reza Eshraghi
- School of Medicine, Kashan University of Medical Sciences, Kashan, Islamic Republic of Iran
| | - Zoha Rahimzadeh
- School of Medicine, Kashan University of Medical Sciences, Kashan, Islamic Republic of Iran
| | - Seyed Gholamabbas Mosavi
- Biostatistics Group, Health Faculty, Kashan University of Medical Sciences, Kashan, Islamic Republic of Iran
| | - Pouya Goleij
- Department of Genetics, Faculty of Biology, Sana Institute of Higher Education, Sari, Islamic Republic of Iran
| | - Aryan Rezaee
- Student Research Committee, School of Medicine, Iran University of Medical Sciences, Tehran, Islamic Republic of Iran.
| | - Hamed Mirzaei
- Research Center for Biochemistry and Nutrition in Metabolic Diseases, Institute for Basic Sciences, Kashan University, Kashan, Islamic Republic of Iran.
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28
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Ravera S, Bertola N, Puddu A, Bruno S, Maggi D, Panfoli I. Crosstalk between the Rod Outer Segments and Retinal Pigmented Epithelium in the Generation of Oxidative Stress in an In Vitro Model. Cells 2023; 12:2173. [PMID: 37681906 PMCID: PMC10487269 DOI: 10.3390/cells12172173] [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: 06/27/2023] [Revised: 08/21/2023] [Accepted: 08/22/2023] [Indexed: 09/09/2023] Open
Abstract
Dysfunction of the retinal pigment epithelium (RPE) is associated with several diseases characterized by retinal degeneration, such as diabetic retinopathy (DR). However, it has recently been proposed that outer retinal neurons also participate in the damage triggering. Therefore, we have evaluated the possible crosstalk between RPE and photoreceptors in priming and maintaining oxidative damage of the RPE. For this purpose, we used ARPE-19 cells as a model of human RPE, grown in normal (NG, 5.6 mM) or high glucose (HG, 25 mM) and unoxidized (UOx) or oxidized (Ox) mammalian retinal rod outer segments (OSs). ARPE-19 cells were efficient at phagocytizing rod OSs in both NG and HG settings. However, in HG, ARPE-19 cells treated with Ox-rod OSs accumulated MDA and lipofuscins and displayed altered LC3, GRP78, and caspase 8 expression compared to untreated and UOx-rod-OS-treated cells. Data suggest that early oxidative damage may originate from the photoreceptors and subsequently extend to the RPE, providing a new perspective to the idea that retinal degeneration depends solely on a redox alteration of the RPE.
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Affiliation(s)
- Silvia Ravera
- Department of Experimental Medicine, Università di Genoa, Via De Toni 14, 16132 Genova, Italy
| | - Nadia Bertola
- Molecular Pathology Unit, IRCCS Ospedale Policlinico San Martino, Largo Rosanna Benzi 10, 16132 Genova, Italy
| | - Alessandra Puddu
- Department of Internal Medicine and Medical Specialties, University of Genova, Viale Benedetto XV 6, 16132 Genova, Italy
| | - Silvia Bruno
- Department of Experimental Medicine, Università di Genoa, Via De Toni 14, 16132 Genova, Italy
| | - Davide Maggi
- Department of Internal Medicine and Medical Specialties, University of Genova, Viale Benedetto XV 6, 16132 Genova, Italy
| | - Isabella Panfoli
- Department of Pharmacy-(DIFAR), Università di Genova, Viale Benedetto XV 3, 16132 Genova, Italy
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29
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Rosa JGS, Disner GR, Pinto FJ, Lima C, Lopes-Ferreira M. Revisiting Retinal Degeneration Hallmarks: Insights from Molecular Markers and Therapy Perspectives. Int J Mol Sci 2023; 24:13079. [PMID: 37685886 PMCID: PMC10488251 DOI: 10.3390/ijms241713079] [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: 07/06/2023] [Revised: 08/04/2023] [Accepted: 08/14/2023] [Indexed: 09/10/2023] Open
Abstract
Visual impairment and blindness are a growing public health problem as they reduce the life quality of millions of people. The management and treatment of these diseases represent scientific and therapeutic challenges because different cellular and molecular actors involved in the pathophysiology are still being identified. Visual system components, particularly retinal cells, are extremely sensitive to genetic or metabolic alterations, and immune responses activated by local insults contribute to biological events, culminating in vision loss and irreversible blindness. Several ocular diseases are linked to retinal cell loss, and some of them, such as retinitis pigmentosa, age-related macular degeneration, glaucoma, and diabetic retinopathy, are characterized by pathophysiological hallmarks that represent possibilities to study and develop novel treatments for retinal cell degeneration. Here, we present a compilation of revisited information on retinal degeneration, including pathophysiological and molecular features and biochemical hallmarks, and possible research directions for novel treatments to assist as a guide for innovative research. The knowledge expansion upon the mechanistic bases of the pathobiology of eye diseases, including information on complex interactions of genetic predisposition, chronic inflammation, and environmental and aging-related factors, will prompt the identification of new therapeutic strategies.
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Affiliation(s)
| | | | | | | | - Monica Lopes-Ferreira
- Immunoregulation Unit, Laboratory of Applied Toxinology (CeTICs/FAPESP), Butantan Institute, São Paulo 05503900, Brazil; (J.G.S.R.); (G.R.D.); (F.J.P.); (C.L.)
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30
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Li Y, Baccouche B, Del-Risco N, Park J, Song A, McAnany JJ, Kazlauskas A. The Slow Progression of Diabetic Retinopathy Is Associated with Transient Protection of Retinal Vessels from Death. Int J Mol Sci 2023; 24:10869. [PMID: 37446043 PMCID: PMC10341443 DOI: 10.3390/ijms241310869] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2023] [Revised: 06/22/2023] [Accepted: 06/23/2023] [Indexed: 07/15/2023] Open
Abstract
The purpose of this study was to investigate the reason that diabetic retinopathy (DR) is delayed from the onset of diabetes (DM) in diabetic mice. To this end, we tested the hypothesis that the deleterious effects of DM are initially tolerated because endogenous antioxidative defense is elevated and thereby confers resistance to oxidative stress-induced death. We found that this was indeed the case in both type 1 DM (T1D) and type 2 DM (T2D) mouse models. The retinal expression of antioxidant defense genes was increased soon after the onset of DM. In addition, ischemia/oxidative stress caused less death in the retinal vasculature of DM versus non-DM mice. Further investigation with T1D mice revealed that protection was transient; it waned as the duration of DM was prolonged. Finally, a loss of protection was associated with the manifestation of both neural and vascular abnormalities that are diagnostic of DR in mice. These observations demonstrate that DM can transiently activate protection from oxidative stress, which is a plausible explanation for the delay in the development of DR from the onset of DM.
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Affiliation(s)
- Yanliang Li
- Department of Ophthalmology and Visual Sciences, University of Illinois at Chicago, Chicago, IL 60612, USA; (Y.L.); (B.B.); (N.D.-R.); (J.P.); (A.S.); (J.J.M.)
| | - Basma Baccouche
- Department of Ophthalmology and Visual Sciences, University of Illinois at Chicago, Chicago, IL 60612, USA; (Y.L.); (B.B.); (N.D.-R.); (J.P.); (A.S.); (J.J.M.)
| | - Norma Del-Risco
- Department of Ophthalmology and Visual Sciences, University of Illinois at Chicago, Chicago, IL 60612, USA; (Y.L.); (B.B.); (N.D.-R.); (J.P.); (A.S.); (J.J.M.)
| | - Jason Park
- Department of Ophthalmology and Visual Sciences, University of Illinois at Chicago, Chicago, IL 60612, USA; (Y.L.); (B.B.); (N.D.-R.); (J.P.); (A.S.); (J.J.M.)
| | - Amy Song
- Department of Ophthalmology and Visual Sciences, University of Illinois at Chicago, Chicago, IL 60612, USA; (Y.L.); (B.B.); (N.D.-R.); (J.P.); (A.S.); (J.J.M.)
| | - J. Jason McAnany
- Department of Ophthalmology and Visual Sciences, University of Illinois at Chicago, Chicago, IL 60612, USA; (Y.L.); (B.B.); (N.D.-R.); (J.P.); (A.S.); (J.J.M.)
| | - Andrius Kazlauskas
- Department of Ophthalmology and Visual Sciences, University of Illinois at Chicago, Chicago, IL 60612, USA; (Y.L.); (B.B.); (N.D.-R.); (J.P.); (A.S.); (J.J.M.)
- Department of Physiology and Biophysics, University of Illinois at Chicago, Chicago, IL 60612, USA
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31
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Liu L, Qin M, Ji J, Wang W. Correlation between hearing impairment and the Triglyceride Glucose Index: based on a national cross-sectional study. Front Endocrinol (Lausanne) 2023; 14:1216718. [PMID: 37424854 PMCID: PMC10325635 DOI: 10.3389/fendo.2023.1216718] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/04/2023] [Accepted: 06/06/2023] [Indexed: 07/11/2023] Open
Abstract
Objective Data from the National Health and Nutrition Examination Survey (NHANES) were used to assess the association between the triglyceride-glucose (TyG) index and hearing impairment (HI). Methods We used eight survey cycles from NHANES 2001-2012 and 2015-2018 to conduct this cross-sectional study. HI was designed as an dependent variable, and the TyG index was selected as an exposure factor (independent variable). The correlation between the two variables was assessed using multiple logistic regression. In order to assess whether there was a non-linear relationship between the TyG index and HI, the TyG index was distributed and a test for trend was conducted (P for trend), followed by smooth curve fitting (penalized spline) and generalized additive model (GAM) regression. We also performed a subgroup analysis to identify sensitive groups whose responses were clearly associated with independent variables. Results 10,906 participants were finally included in the study, and those with a higher TyG index had a higher frequency of hearing impairment. There was a linear positive correlation between the TyG index and HI. For the low-frequency HI, however, this positive correlation was not statistically significant (OR = 1.05, 95% CI: 0.98, 1.14); however, it was more stable for the high-frequency HI (OR = 1.12, 95% CI: 1.03, 1.22). Additionally, as the TyG index increased, this positive association increased as well (P for trend = 0.05). The HPTA test showed a positive association with more severe HI (simultaneous) as the independent variable increased (OR = 1.14, 95% CI: 1.05-1.24), and this association was even more significant with increasing severity (P for trend 0.05). According to the subgroup analysis, the positive association between TyG index and high-frequency HI was more significant in females, 40-69 years old, without hypertension or diabetes, and when strict high-frequency HI was significant in males, females, 40-69 years old, with hypertension and diabetes. Conclusion Participants with a higher TyG index may have a higher risk of HI. TyG index and HI risk showed a linear relationship, which became even more significant when HPTA was included.
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Affiliation(s)
- Long Liu
- Department Otorhinolaryngology, Head and Neck Surgery, The Second Affiliated Hospital of Anhui Medical University, Hefei, Anhui, China
| | - Maolin Qin
- Department Otorhinolaryngology, Head and Neck Surgery, Wuhu Hospital, East China Normal University (The Second People’s Hospital of Wuhu), Wuhu, Anhui, China
| | - Jiabiao Ji
- Department Otorhinolaryngology, Head and Neck Surgery, The Second Affiliated Hospital of Anhui Medical University, Hefei, Anhui, China
| | - Weiqing Wang
- Department Otorhinolaryngology, Head and Neck Surgery, The Second Affiliated Hospital of Anhui Medical University, Hefei, Anhui, China
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Alka K, Kumar J, Kowluru RA. Impaired mitochondrial dynamics and removal of the damaged mitochondria in diabetic retinopathy. Front Endocrinol (Lausanne) 2023; 14:1160155. [PMID: 37415667 PMCID: PMC10320727 DOI: 10.3389/fendo.2023.1160155] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/06/2023] [Accepted: 06/01/2023] [Indexed: 07/08/2023] Open
Abstract
Introduction Mitochondrial dynamic plays a major role in their quality control, and the damaged mitochondrial components are removed by autophagy. In diabetic retinopathy, mitochondrial fusion enzyme, mitofusin 2 (Mfn2), is downregulated and mitochondrial dynamic is disturbed resulting in depolarized and dysfunctional mitochondria. Our aim was to investigate the mechanism of inhibition of Mfn2, and its role in the removal of the damaged mitochondria, in diabetic retinopathy. Methods Using human retinal endothelial cells, effect of high glucose (20mM) on the GTPase activity of Mfn2 and its acetylation were determined. Role of Mfn2 in the removal of the damaged mitochondria was confirmed by regulating its acetylation, or by Mfn2 overexpression, on autophagosomes- autolysosomes formation and the mitophagy flux. Results High glucose inhibited GTPase activity and increased acetylation of Mfn2. Inhibition of acetylation, or Mfn2 overexpression, attenuated decrease in GTPase activity and mitochondrial fragmentation, and increased the removal of the damaged mitochondria. Similar phenomenon was observed in diabetic mice; overexpression of sirtuin 1 (a deacetylase) ameliorated diabetes-induced inhibition of retinal Mfn2 and facilitated the removal of the damaged mitochondria. Conclusions Acetylation of Mfn2 has dual roles in mitochondrial homeostasis in diabetic retinopathy, it inhibits GTPase activity of Mfn2 and increases mitochondrial fragmentation, and also impairs removal of the damaged mitochondria. Thus, protecting Mfn2 activity should maintain mitochondrial homeostasis and inhibit the development/progression of diabetic retinopathy.
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Affiliation(s)
| | | | - Renu A. Kowluru
- Ophthalmology, Visual and Anatomical Sciences, Wayne State University, Detroit, MI, United States
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Jamrozik D, Dutczak R, Machowicz J, Wojtyniak A, Smędowski A, Pietrucha-Dutczak M. Metallothioneins, a Part of the Retinal Endogenous Protective System in Various Ocular Diseases. Antioxidants (Basel) 2023; 12:1251. [PMID: 37371981 DOI: 10.3390/antiox12061251] [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: 04/26/2023] [Revised: 06/01/2023] [Accepted: 06/08/2023] [Indexed: 06/29/2023] Open
Abstract
Metallothioneins are the metal-rich proteins that play important roles in metal homeostasis and detoxification. Moreover, these proteins protect cells against oxidative stress, inhibit proapoptotic mechanisms and enhance cell differentiation and survival. Furthermore, MTs, mainly MT-1/2 and MT-3, play a vital role in protecting the neuronal retinal cells in the eye. Expression disorders of these proteins may be responsible for the development of various age-related eye diseases, including glaucoma, age-related macular degeneration, diabetic retinopathy and retinitis pigmentosa. In this review, we focused on the literature reports suggesting that these proteins may be a key component of the endogenous protection system of the retinal neurons, and, when the expression of MTs is disrupted, this system becomes inefficient. Moreover, we described the location of different MT isoforms in ocular tissues. Then we discussed the changes in MT subtypes' expression in the context of the common eye diseases. Finally, we highlighted the possibility of the use of MTs as biomarkers for cancer diagnosis.
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Affiliation(s)
- Daniel Jamrozik
- Department of Physiology, Faculty of Medical Sciences in Katowice, Medical University of Silesia, Medyków 18, 40-752 Katowice, Poland
| | - Radosław Dutczak
- Department of Physiology, Faculty of Medical Sciences in Katowice, Medical University of Silesia, Medyków 18, 40-752 Katowice, Poland
| | - Joanna Machowicz
- Department of Physiology, Faculty of Medical Sciences in Katowice, Medical University of Silesia, Medyków 18, 40-752 Katowice, Poland
| | - Alicja Wojtyniak
- Department of Physiology, Faculty of Medical Sciences in Katowice, Medical University of Silesia, Medyków 18, 40-752 Katowice, Poland
| | - Adrian Smędowski
- Department of Physiology, Faculty of Medical Sciences in Katowice, Medical University of Silesia, Medyków 18, 40-752 Katowice, Poland
- GlaucoTech Co., Gen., Władysława Sikorskiego 45/177, 40-282 Katowice, Poland
| | - Marita Pietrucha-Dutczak
- Department of Physiology, Faculty of Medical Sciences in Katowice, Medical University of Silesia, Medyków 18, 40-752 Katowice, Poland
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34
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Kowluru RA, Alka K. Mitochondrial Quality Control and Metabolic Memory Phenomenon Associated with Continued Progression of Diabetic Retinopathy. Int J Mol Sci 2023; 24:ijms24098076. [PMID: 37175784 PMCID: PMC10179288 DOI: 10.3390/ijms24098076] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2023] [Revised: 04/17/2023] [Accepted: 04/19/2023] [Indexed: 05/15/2023] Open
Abstract
Diabetic retinopathy continues to progress even when hyperglycemia is terminated, suggesting a 'metabolic memory' phenomenon. Mitochondrial dysfunction is closely associated with the development of diabetic retinopathy, and mitochondria remain dysfunctional. Quality control of mitochondria requires a fine balance between mitochondrial fission-fusion, removal of the damaged mitochondria (mitophagy) and formation of new mitochondria (biogenesis). In diabetes, while mitochondrial fusion protein (Mfn2) is decreased, fission protein (Drp1) is increased, resulting in fragmented mitochondria. Re-institution of normal glycemia fails to reverse mitochondrial fragmentation, and dysfunctional mitochondria continue to accumulate. Our aim was to investigate the direct effect of regulation of the mitochondrial fusion process during normal glycemia that follows a high glucose insult on mitochondrial quality control in the 'metabolic memory' phenomenon. Human retinal endothelial cells, incubated in 20 mM glucose for four days, followed by 5 mM glucose for four additional days, with or without the Mfn2 activator leflunomide, were analyzed for mitochondrial fission (live cell imaging), mitophagy (flow cytometry and immunofluorescence microscopy), and mitochondrial mass (mitochondrial copy numbers and MitoTracker labeling). Mitochondrial health was determined by quantifying mitochondrial reactive oxygen species (ROS), respiration rate (Seahorse XF96) and mitochondrial DNA (mtDNA) damage. Addition of leflunomide during normal glucose exposure that followed high glucose prevented mitochondrial fission, facilitated mitophagy and increased mitochondrial mass. Glucose-induced decrease in mitochondrial respiration and increase in ROS and mtDNA damage were also prevented. Thus, direct regulation of mitochondrial dynamics can help maintain mitochondrial quality control and interfere with the metabolic memory phenomenon, preventing further progression of diabetic retinopathy.
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Affiliation(s)
- Renu A Kowluru
- Department of Ophthalmology, Visual and Anatomical Sciences, Wayne State University, Detroit, MI 48201, USA
| | - Kumari Alka
- Department of Ophthalmology, Visual and Anatomical Sciences, Wayne State University, Detroit, MI 48201, USA
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35
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Bai L, Zhou Y, Zhang J, Ma J. The Role of a Ketogenic Diet in the Treatment of Dementia in Type 2 Diabetes Mellitus. Nutrients 2023; 15:nu15081971. [PMID: 37111190 PMCID: PMC10142932 DOI: 10.3390/nu15081971] [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: 03/16/2023] [Revised: 04/15/2023] [Accepted: 04/17/2023] [Indexed: 04/29/2023] Open
Abstract
Type 2 diabetes mellitus (T2DM) shares a common molecular mechanism and underlying pathology with dementia, and studies indicate that dementia is widespread in people with T2DM. Currently, T2DM-induced cognitive impairment is characterized by altered insulin and cerebral glucose metabolism, leading to a shorter life span. Increasing evidence indicates that nutritional and metabolic treatments can possibly alleviate these issues, as there is a lack of efficient preventative and treatment methods. The ketogenic diet (KD) is a very high-fat, low-carbohydrate diet that induces ketosis in the body by producing a fasting-like effect, and neurons in the aged brain are protected from damage by ketone bodies. Moreover, the creation of ketone bodies may improve brain neuronal function, decrease inflammatory expression and reactive oxygen species (ROS) production, and restore neuronal metabolism. As a result, the KD has drawn attention as a potential treatment for neurological diseases, such as T2DM-induced dementia. This review aims to examine the role of the KD in the prevention of dementia risk in T2DM patients and to outline specific aspects of the neuroprotective effects of the KD, providing a rationale for the implementation of dietary interventions as a therapeutic strategy for T2DM-induced dementia in the future.
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Affiliation(s)
- Lin Bai
- Department of Neurosurgery, West China Hospital of Sichuan University, Chengdu 610041, China
- Key Laboratory of Transplant Engineering and Immunology, NHFPC, West China Hospital of Sichuan University, Chengdu 610041, China
- Core Facility of West China Hospital of Sichuan University, Chengdu 610041, China
| | - Yue Zhou
- Department of Pharmacy, Xindu District People's Hospital of Chengdu, Chengdu 610500, China
| | - Jie Zhang
- Key Laboratory of Transplant Engineering and Immunology, NHFPC, West China Hospital of Sichuan University, Chengdu 610041, China
- Core Facility of West China Hospital of Sichuan University, Chengdu 610041, China
| | - Junpeng Ma
- Department of Neurosurgery, West China Hospital of Sichuan University, Chengdu 610041, China
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36
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Wang J, Feng S, Zhang Q, Qin H, Xu C, Fu X, Yan L, Zhao Y, Yao K. Roles of Histone Acetyltransferases and Deacetylases in the Retinal Development and Diseases. Mol Neurobiol 2023; 60:2330-2354. [PMID: 36637745 DOI: 10.1007/s12035-023-03213-1] [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: 10/26/2022] [Accepted: 01/04/2023] [Indexed: 01/14/2023]
Abstract
The critical role of epigenetic modification of histones in maintaining the normal function of the nervous system has attracted increasing attention. Among these modifications, the level of histone acetylation, modulated by histone acetyltransferases (HATs) and histone deacetylases (HDACs), is essential in regulating gene expression. In recent years, the research progress on the function of HDACs in retinal development and disease has advanced remarkably, while that regarding HATs remains to be investigated. Here, we overview the roles of HATs and HDACs in regulating the development of diverse retinal cells, including retinal progenitor cells, photoreceptor cells, bipolar cells, ganglion cells, and Müller glial cells. The effects of HATs and HDACs on the progression of various retinal diseases are also discussed with the highlight of the proof-of-concept research regarding the application of available HDAC inhibitors in treating retinal diseases.
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Affiliation(s)
- Jingjing Wang
- Institute of Visual Neuroscience and Stem Cell Engineering, Wuhan University of Science and Technology, Wuhan, 430065, China.,College of Life Sciences and Health, Wuhan University of Science and Technology, Wuhan, 430065, China
| | - Shuyu Feng
- Institute of Visual Neuroscience and Stem Cell Engineering, Wuhan University of Science and Technology, Wuhan, 430065, China.,College of Life Sciences and Health, Wuhan University of Science and Technology, Wuhan, 430065, China
| | - Qian Zhang
- Institute of Visual Neuroscience and Stem Cell Engineering, Wuhan University of Science and Technology, Wuhan, 430065, China.,College of Life Sciences and Health, Wuhan University of Science and Technology, Wuhan, 430065, China
| | - Huan Qin
- Institute of Visual Neuroscience and Stem Cell Engineering, Wuhan University of Science and Technology, Wuhan, 430065, China.,College of Life Sciences and Health, Wuhan University of Science and Technology, Wuhan, 430065, China
| | - Chunxiu Xu
- Institute of Visual Neuroscience and Stem Cell Engineering, Wuhan University of Science and Technology, Wuhan, 430065, China.,College of Life Sciences and Health, Wuhan University of Science and Technology, Wuhan, 430065, China
| | - Xuefei Fu
- Institute of Visual Neuroscience and Stem Cell Engineering, Wuhan University of Science and Technology, Wuhan, 430065, China.,College of Life Sciences and Health, Wuhan University of Science and Technology, Wuhan, 430065, China
| | - Lin Yan
- Institute of Visual Neuroscience and Stem Cell Engineering, Wuhan University of Science and Technology, Wuhan, 430065, China.,College of Life Sciences and Health, Wuhan University of Science and Technology, Wuhan, 430065, China
| | - Yaqin Zhao
- Institute of Visual Neuroscience and Stem Cell Engineering, Wuhan University of Science and Technology, Wuhan, 430065, China.,College of Life Sciences and Health, Wuhan University of Science and Technology, Wuhan, 430065, China
| | - Kai Yao
- Institute of Visual Neuroscience and Stem Cell Engineering, Wuhan University of Science and Technology, Wuhan, 430065, China. .,College of Life Sciences and Health, Wuhan University of Science and Technology, Wuhan, 430065, China. .,Hubei Province Key Laboratory of Occupational Hazard Identification and Control, Wuhan University of Science and Technology, Wuhan, 430065, China.
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37
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Patel C, Pande S, Sagathia V, Ranch K, Beladiya J, Boddu SHS, Jacob S, Al-Tabakha MM, Hassan N, Shahwan M. Nanocarriers for the Delivery of Neuroprotective Agents in the Treatment of Ocular Neurodegenerative Diseases. Pharmaceutics 2023; 15:837. [PMID: 36986699 PMCID: PMC10052766 DOI: 10.3390/pharmaceutics15030837] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2023] [Revised: 02/25/2023] [Accepted: 03/02/2023] [Indexed: 03/08/2023] Open
Abstract
Retinal neurodegeneration is considered an early event in the pathogenesis of several ocular diseases, such as diabetic retinopathy, age-related macular degeneration, and glaucoma. At present, there is no definitive treatment to prevent the progression or reversal of vision loss caused by photoreceptor degeneration and the death of retinal ganglion cells. Neuroprotective approaches are being developed to increase the life expectancy of neurons by maintaining their shape/function and thus prevent the loss of vision and blindness. A successful neuroprotective approach could prolong patients' vision functioning and quality of life. Conventional pharmaceutical technologies have been investigated for delivering ocular medications; however, the distinctive structural characteristics of the eye and the physiological ocular barriers restrict the efficient delivery of drugs. Recent developments in bio-adhesive in situ gelling systems and nanotechnology-based targeted/sustained drug delivery systems are receiving a lot of attention. This review summarizes the putative mechanism, pharmacokinetics, and mode of administration of neuroprotective drugs used to treat ocular disorders. Additionally, this review focuses on cutting-edge nanocarriers that demonstrated promising results in treating ocular neurodegenerative diseases.
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Affiliation(s)
- Chirag Patel
- Department of Pharmacology, L. M. College of Pharmacy, Ahmedabad 380009, India
| | - Sonal Pande
- Department of Pharmacology, L. M. College of Pharmacy, Ahmedabad 380009, India
| | - Vrunda Sagathia
- Department of Pharmacology, L. M. College of Pharmacy, Ahmedabad 380009, India
| | - Ketan Ranch
- Department of Pharmaceutics, L. M. College of Pharmacy, Ahmedabad 380009, India
| | - Jayesh Beladiya
- Department of Pharmacology, L. M. College of Pharmacy, Ahmedabad 380009, India
| | - Sai H. S. Boddu
- Department of Pharmaceutical Sciences, College of Pharmacy and Health Sciences, Ajman University, Ajman P.O. Box 346, United Arab Emirates
- Center of Medical and Bio-Allied Health Sciences Research, Ajman University, Ajman P.O. Box 346, United Arab Emirates
| | - Shery Jacob
- Department of Pharmaceutical Sciences, College of Pharmacy, Gulf Medical University, Ajman P.O. Box 4184, United Arab Emirates
| | - Moawia M. Al-Tabakha
- Department of Pharmaceutical Sciences, College of Pharmacy and Health Sciences, Ajman University, Ajman P.O. Box 346, United Arab Emirates
- Center of Medical and Bio-Allied Health Sciences Research, Ajman University, Ajman P.O. Box 346, United Arab Emirates
| | - Nageeb Hassan
- Center of Medical and Bio-Allied Health Sciences Research, Ajman University, Ajman P.O. Box 346, United Arab Emirates
- Department of Clinical Sciences, College of Pharmacy & Health Science, Ajman University, Ajman P.O. Box 346, United Arab Emirates
| | - Moyad Shahwan
- Center of Medical and Bio-Allied Health Sciences Research, Ajman University, Ajman P.O. Box 346, United Arab Emirates
- Department of Clinical Sciences, College of Pharmacy & Health Science, Ajman University, Ajman P.O. Box 346, United Arab Emirates
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38
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Zhao B, Zhu L, Ye M, Lou X, Mou Q, Hu Y, Zhang H, Zhao Y. Oxidative stress and epigenetics in ocular vascular aging: an updated review. Mol Med 2023; 29:28. [PMID: 36849907 PMCID: PMC9972630 DOI: 10.1186/s10020-023-00624-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2022] [Accepted: 02/16/2023] [Indexed: 03/01/2023] Open
Abstract
Vascular aging is an inevitable process with advancing age, which plays a crucial role in the pathogenesis of cardiovascular and microvascular diseases. Diabetic retinopathy (DR) and age-related macular degeneration (AMD), characterized by microvascular dysfunction, are the common causes of irreversible blindness worldwide, however there is still a lack of effective therapeutic strategies for rescuing the visual function. In order to develop novel treatments, it is essential to illuminate the pathological mechanisms underlying the vascular aging during DR and AMD progression. In this review, we have summarized the recent discoveries of the effects of oxidative stress and epigenetics on microvascular degeneration, which could provide potential therapeutic targets for DR and AMD.
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Affiliation(s)
- Bowen Zhao
- Department of Ophthalmology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030, China
| | - Lijia Zhu
- Department of Ophthalmology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030, China
| | - Meng Ye
- Department of Ophthalmology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030, China
| | - Xiaotong Lou
- Department of Ophthalmology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030, China
| | - Qianxue Mou
- Department of Ophthalmology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030, China
| | - Yuanyuan Hu
- Department of Ophthalmology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030, China
| | - Hong Zhang
- Department of Ophthalmology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030, China.
| | - Yin Zhao
- Department of Ophthalmology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030, China.
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39
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Towards a New Biomarker for Diabetic Retinopathy: Exploring RBP3 Structure and Retinoids Binding for Functional Imaging of Eyes In Vivo. Int J Mol Sci 2023; 24:ijms24054408. [PMID: 36901838 PMCID: PMC10002987 DOI: 10.3390/ijms24054408] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2022] [Revised: 02/10/2023] [Accepted: 02/21/2023] [Indexed: 02/25/2023] Open
Abstract
Diabetic retinopathy (DR) is a severe disease with a growing number of afflicted patients, which places a heavy burden on society, both socially and financially. While there are treatments available, they are not always effective and are usually administered when the disease is already at a developed stage with visible clinical manifestation. However, homeostasis at a molecular level is disrupted before visible signs of the disease are evident. Thus, there has been a constant search for effective biomarkers that could signal the onset of DR. There is evidence that early detection and prompt disease control are effective in preventing or slowing DR progression. Here, we review some of the molecular changes that occur before clinical manifestations are observable. As a possible new biomarker, we focus on retinol binding protein 3 (RBP3). We argue that it displays unique features that make it a very good biomarker for non-invasive, early-stage DR detection. Linking chemistry to biological function and focusing on new developments in eye imaging and two-photon technology, we describe a new potential diagnostic tool that would allow rapid and effective quantification of RBP3 in the retina. Moreover, this tool would also be useful in the future to monitor therapeutic effectiveness if levels of RBP3 are elevated by DR treatments.
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40
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Song YS, Zaitoun IS, Wang S, Darjatmoko SR, Sorenson CM, Sheibani N. Cytochrome P450 1B1 Expression Regulates Intracellular Iron Levels and Oxidative Stress in the Retinal Endothelium. Int J Mol Sci 2023; 24:2420. [PMID: 36768740 PMCID: PMC9916835 DOI: 10.3390/ijms24032420] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2022] [Revised: 01/20/2023] [Accepted: 01/24/2023] [Indexed: 01/28/2023] Open
Abstract
Cytochrome P450 (CYP) 1B1 is a heme-containing monooxygenase found mainly in extrahepatic tissues, including the retina. CYP1B1 substrates include exogenous aromatic hydrocarbons, such as dioxins, and endogenous bioactive compounds, including 17β-estradiol (E2) and arachidonic acid. The endogenous compounds and their metabolites are mediators of various cellular and physiological processes, suggesting that CYP1B1 activity is likely important in maintaining proper cellular and tissue functions. We previously demonstrated that lack of CYP1B1 expression and activity are associated with increased levels of reactive oxygen species and oxidative stress in the retinal vasculature and vascular cells, including retinal endothelial cells (ECs). However, the detailed mechanism(s) of how CYP1B1 activity modulates redox homeostasis remained unknown. We hypothesized that CYP1B1 metabolism of E2 affects bone morphogenic protein 6 (BMP6)-hepcidin-mediated iron homeostasis and lipid peroxidation impacting cellular redox state. Here, we demonstrate retinal EC prepared from Cyp1b1-deficient (Cyp1b1-/-) mice exhibits increased estrogen receptor-α (ERα) activity and expresses higher levels of BMP6. BMP6 is an inducer of the iron-regulatory hormone hepcidin in the endothelium. Increased hepcidin expression in Cyp1b1-/- retinal EC resulted in decreased levels of the iron exporter protein ferroportin and, as a result, increased intracellular iron accumulation. Removal of excess iron or antagonism of ERα in Cyp1b1-/- retinal EC was sufficient to mitigate increased lipid peroxidation and reduce oxidative stress. Suppression of lipid peroxidation and antagonism of ERα also restored ischemia-mediated retinal neovascularization in Cyp1b1-/- mice. Thus, CYP1B1 expression in retinal EC is important in the regulation of intracellular iron levels, with a significant impact on ocular redox homeostasis and oxidative stress through modulation of the ERα/BMP6/hepcidin axis.
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Affiliation(s)
- Yong-Seok Song
- Department of Ophthalmology and Visual Sciences, University of Wisconsin School of Medicine and Public Health, Madison, WI 53705, USA
- McPherson Eye Research Institute, University of Wisconsin School of Medicine and Public Health, Madison, WI 53705, USA
| | - Ismail S. Zaitoun
- Department of Ophthalmology and Visual Sciences, University of Wisconsin School of Medicine and Public Health, Madison, WI 53705, USA
- McPherson Eye Research Institute, University of Wisconsin School of Medicine and Public Health, Madison, WI 53705, USA
| | - Shoujian Wang
- Department of Ophthalmology and Visual Sciences, University of Wisconsin School of Medicine and Public Health, Madison, WI 53705, USA
- McPherson Eye Research Institute, University of Wisconsin School of Medicine and Public Health, Madison, WI 53705, USA
| | - Soesiawati R. Darjatmoko
- Department of Ophthalmology and Visual Sciences, University of Wisconsin School of Medicine and Public Health, Madison, WI 53705, USA
- McPherson Eye Research Institute, University of Wisconsin School of Medicine and Public Health, Madison, WI 53705, USA
| | - Christine M. Sorenson
- McPherson Eye Research Institute, University of Wisconsin School of Medicine and Public Health, Madison, WI 53705, USA
- Department of Pediatrics, University of Wisconsin School of Medicine and Public Health, Madison, WI 53705, USA
| | - Nader Sheibani
- Department of Ophthalmology and Visual Sciences, University of Wisconsin School of Medicine and Public Health, Madison, WI 53705, USA
- McPherson Eye Research Institute, University of Wisconsin School of Medicine and Public Health, Madison, WI 53705, USA
- Department of Cell and Regenerative Biology, University of Wisconsin School of Medicine and Public Health, Madison, WI 53705, USA
- Department of Biomedical Engineering, University of Wisconsin, Madison, WI 53705, USA
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41
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Kowluru RA. Cross Talks between Oxidative Stress, Inflammation and Epigenetics in Diabetic Retinopathy. Cells 2023; 12:300. [PMID: 36672234 PMCID: PMC9857338 DOI: 10.3390/cells12020300] [Citation(s) in RCA: 17] [Impact Index Per Article: 17.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2022] [Revised: 01/06/2023] [Accepted: 01/10/2023] [Indexed: 01/15/2023] Open
Abstract
Diabetic retinopathy, one of the most devastating complications of diabetes, is a multifactorial progressing disease with a very complex etiology. Although many metabolic, molecular, functional and structural changes have been identified in the retina and its vasculature, the exact molecular mechanism of its pathogenesis still remains elusive. Sustained high-circulating glucose increases oxidative stress in the retina and also activates the inflammatory cascade. Free radicals increase inflammatory mediators, and inflammation can increase production of free radicals, suggesting a positive loop between them. In addition, diabetes also facilitates many epigenetic modifications that can influence transcription of a gene without changing the DNA sequence. Several genes associated with oxidative stress and inflammation in the pathogenesis of diabetic retinopathy are also influenced by epigenetic modifications. This review discusses cross-talks between oxidative stress, inflammation and epigenetics in diabetic retinopathy. Since epigenetic changes are influenced by external factors such as environment and lifestyle, and they can also be reversed, this opens up possibilities for new strategies to inhibit the development/progression of this sight-threatening disease.
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Affiliation(s)
- Renu A Kowluru
- Department of Ophthalmology, Visual and Anatomical Sciences, Wayne State University, Detroit, MI 48201, USA
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42
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Zhang Z, Huang Q, Zhao D, Lian F, Li X, Qi W. The impact of oxidative stress-induced mitochondrial dysfunction on diabetic microvascular complications. Front Endocrinol (Lausanne) 2023; 14:1112363. [PMID: 36824356 PMCID: PMC9941188 DOI: 10.3389/fendo.2023.1112363] [Citation(s) in RCA: 16] [Impact Index Per Article: 16.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/30/2022] [Accepted: 01/24/2023] [Indexed: 02/10/2023] Open
Abstract
Diabetes mellitus (DM) is a metabolic disease characterized by chronic hyperglycaemia, with absolute insulin deficiency or insulin resistance as the main cause, and causes damage to various target organs including the heart, kidney and neurovascular. In terms of the pathological and physiological mechanisms of DM, oxidative stress is one of the main mechanisms leading to DM and is an important link between DM and its complications. Oxidative stress is a pathological phenomenon resulting from an imbalance between the production of free radicals and the scavenging of antioxidant systems. The main site of reactive oxygen species (ROS) production is the mitochondria, which are also the main organelles damaged. In a chronic high glucose environment, impaired electron transport chain within the mitochondria leads to the production of ROS, prompts increased proton leakage and altered mitochondrial membrane potential (MMP), which in turn releases cytochrome c (cyt-c), leading to apoptosis. This subsequently leads to a vicious cycle of impaired clearance by the body's antioxidant system, impaired transcription and protein synthesis of mitochondrial DNA (mtDNA), which is responsible for encoding mitochondrial proteins, and impaired DNA repair systems, contributing to mitochondrial dysfunction. This paper reviews the dysfunction of mitochondria in the environment of high glucose induced oxidative stress in the DM model, and looks forward to providing a new treatment plan for oxidative stress based on mitochondrial dysfunction.
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Affiliation(s)
- Ziwei Zhang
- College of Traditional Chinese Medicine, Changchun University of Chinese Medicine, Changchun, China
| | - Qingxia Huang
- Key Laboratory of Active Substances and Biological Mechanisms of Ginseng Efficacy, Jilin Provincial Key Laboratory of Biomacromolecules of Chinese Medicine, Ministry of Education, Northeast Asia Research Institute of Traditional Chinese Medicine, Changchun University of Chinese Medicine, Changchun, China
- Research Center of Traditional Chinese Medicine, The Affiliated Hospital to Changchun University of Chinese Medicine, Changchun, Jilin, China
| | - Daqing Zhao
- Key Laboratory of Active Substances and Biological Mechanisms of Ginseng Efficacy, Jilin Provincial Key Laboratory of Biomacromolecules of Chinese Medicine, Ministry of Education, Northeast Asia Research Institute of Traditional Chinese Medicine, Changchun University of Chinese Medicine, Changchun, China
| | - Fengmei Lian
- College of Traditional Chinese Medicine, Changchun University of Chinese Medicine, Changchun, China
- Guang’anmen Hospital, China Academy of Chinese Medical Sciences, Beijing, China
- *Correspondence: Fengmei Lian, ; Xiangyan Li, ; Wenxiu Qi,
| | - Xiangyan Li
- Key Laboratory of Active Substances and Biological Mechanisms of Ginseng Efficacy, Jilin Provincial Key Laboratory of Biomacromolecules of Chinese Medicine, Ministry of Education, Northeast Asia Research Institute of Traditional Chinese Medicine, Changchun University of Chinese Medicine, Changchun, China
- *Correspondence: Fengmei Lian, ; Xiangyan Li, ; Wenxiu Qi,
| | - Wenxiu Qi
- Key Laboratory of Active Substances and Biological Mechanisms of Ginseng Efficacy, Jilin Provincial Key Laboratory of Biomacromolecules of Chinese Medicine, Ministry of Education, Northeast Asia Research Institute of Traditional Chinese Medicine, Changchun University of Chinese Medicine, Changchun, China
- *Correspondence: Fengmei Lian, ; Xiangyan Li, ; Wenxiu Qi,
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Dos Santos FM, Ciordia S, Mesquita J, de Sousa JPC, Paradela A, Tomaz CT, Passarinha LAP. Vitreous humor proteome: unraveling the molecular mechanisms underlying proliferative and neovascular vitreoretinal diseases. Cell Mol Life Sci 2022; 80:22. [PMID: 36585968 PMCID: PMC11072707 DOI: 10.1007/s00018-022-04670-y] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2022] [Revised: 11/09/2022] [Accepted: 12/12/2022] [Indexed: 01/01/2023]
Abstract
Proliferative diabetic retinopathy (PDR), proliferative vitreoretinopathy (PVR), and neovascular age-related macular degeneration (nAMD) are among the leading causes of blindness. Due to the multifactorial nature of these vitreoretinal diseases, omics approaches are essential for a deeper understanding of the pathophysiologic processes underlying the evolution to a proliferative or neovascular etiology, in which patients suffer from an abrupt loss of vision. For many years, it was thought that the function of the vitreous was merely structural, supporting and protecting the surrounding ocular tissues. Proteomics studies proved that vitreous is more complex and biologically active than initially thought, and its changes reflect the physiological and pathological state of the eye. The vitreous is the scenario of a complex interplay between inflammation, fibrosis, oxidative stress, neurodegeneration, and extracellular matrix remodeling. Vitreous proteome not only reflects the pathological events that occur in the retina, but the changes in the vitreous itself play a central role in the onset and progression of vitreoretinal diseases. Therefore, this review offers an overview of the studies on the vitreous proteome that could help to elucidate some of the pathological mechanisms underlying proliferative and/or neovascular vitreoretinal diseases and to find new potential pharmaceutical targets.
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Affiliation(s)
- Fátima Milhano Dos Santos
- Health Sciences Research Centre (CICS-UBI), Universidade da Beira Interior, 6201-001, Covilhã, Portugal.
- Functional Proteomics Laboratory, Centro Nacional de Biotecnología (CNB-CSIC), Unidad de Proteomica, Calle Darwin 3, Campus de Cantoblanco, 28049, Madrid, Spain.
| | - Sergio Ciordia
- Functional Proteomics Laboratory, Centro Nacional de Biotecnología (CNB-CSIC), Unidad de Proteomica, Calle Darwin 3, Campus de Cantoblanco, 28049, Madrid, Spain
| | - Joana Mesquita
- Health Sciences Research Centre (CICS-UBI), Universidade da Beira Interior, 6201-001, Covilhã, Portugal
| | - João Paulo Castro de Sousa
- Health Sciences Research Centre (CICS-UBI), Universidade da Beira Interior, 6201-001, Covilhã, Portugal
- Department of Ophthalmology, Centro Hospitalar de Leiria, 2410-197, Leiria, Portugal
| | - Alberto Paradela
- Functional Proteomics Laboratory, Centro Nacional de Biotecnología (CNB-CSIC), Unidad de Proteomica, Calle Darwin 3, Campus de Cantoblanco, 28049, Madrid, Spain
| | - Cândida Teixeira Tomaz
- Health Sciences Research Centre (CICS-UBI), Universidade da Beira Interior, 6201-001, Covilhã, Portugal
- C4-UBI, Cloud Computing Competence Centre, University of Beira Interior, 6200-501, Covilhã, Portugal
- Chemistry Department, Faculty of Sciences, Universidade da Beira Interior, 6201-001, Covilhã, Portugal
| | - Luís António Paulino Passarinha
- Health Sciences Research Centre (CICS-UBI), Universidade da Beira Interior, 6201-001, Covilhã, Portugal.
- Associate Laboratory i4HB, Faculdade de Ciências e Tecnologia, Institute for Health and Bioeconomy, Universidade NOVA, 2819-516, Caparica, Portugal.
- UCIBIO-Applied Molecular Biosciences Unit, Departamento de Química, Faculdade de Ciências e Tecnologia, Universidade NOVA de Lisboa, 2829-516, Caparica, Portugal.
- Pharmaco-Toxicology Laboratory, UBIMedical, Universidade da Beira Interior, 6200-000, Covilhã, Portugal.
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Abnormal Levels of Serum Ferroptosis-Related Biomarkers in Diabetic Retinopathy. J Ophthalmol 2022; 2022:3353740. [PMID: 36620526 PMCID: PMC9822742 DOI: 10.1155/2022/3353740] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2022] [Revised: 11/23/2022] [Accepted: 12/12/2022] [Indexed: 12/31/2022] Open
Abstract
Purpose This study aimed to measure the concentrations of ferroptosis-related biomarkers, namely, iron (Fe), lipid peroxide (LPO), reactive oxygen species (ROS), glutathione peroxidase-4 (GPX4), and glutathione (GSH) in DR in the attempt to evaluate the diagnostic performance of these biomarkers. Methods This study included 30 NPDR patients, 30 PDR patients, and 30 healthy subjects matched in age and sex. The concentrations of Fe, LPO, ROS, GPX4, and GSH in serum of the subjects were measured. Results Compared with the normal group, GPX4 and GSH concentrations were significantly lower, and LPO, Fe, and ROS concentrations were significantly higher in DR patients. Compared with the PDR group, the NPDR group had higher concentrations of LPO, Fe, and ROS and lower concentrations of GPX4 and GSH, but there was no statistical difference in Fe, GPX4, and GSH. ROC curve shows that ferroptosis-related biomarkers have accumulated accuracy in NPDR and PDR. Conclusion This study shows that ferroptosis-related biomarkers may be involved in the pathological process of DR and can be used as one of the biomarkers of DR.
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Serikbaeva A, Li Y, Ganesh B, Zelkha R, Kazlauskas A. Hyperglycemia Promotes Mitophagy and Thereby Mitigates Hyperglycemia-Induced Damage. THE AMERICAN JOURNAL OF PATHOLOGY 2022; 192:1779-1794. [PMID: 36063899 PMCID: PMC9765315 DOI: 10.1016/j.ajpath.2022.08.004] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/26/2022] [Revised: 08/02/2022] [Accepted: 08/17/2022] [Indexed: 12/31/2022]
Abstract
The observation that diabetic retinopathy (DR) typically takes decades to develop suggests the existence of an endogenous system that protects from diabetes-induced damage. To investigate the existance of such a system, primary human retinal endothelial cells were cultured in either normal glucose (5 mmol/L) or high glucose (30 mmol/L; HG). Prolonged exposure to HG was beneficial instead of detrimental. Although tumor necrosis factor-α-induced expression of vascular cell adhesion molecule 1 and intercellular adhesion molecule 1 was unaffected after 1 day of HG, it waned as the exposure to HG was extended. Similarly, oxidative stress-induced death decreased with prolonged exposure to HG. Furthermore, mitochondrial functionality, which was compromised by 1 day of HG, was improved by 10 days of HG, and this change required increased clearance of damaged mitochondria (mitophagy). Finally, antagonizing mitochondrial dynamics compromised the cells' ability to endure HG: susceptibility to cell death increased, and basal barrier function and responsiveness to vascular endothelial growth factor deteriorated. These observations indicate the existence of an endogenous system that protects human retinal endothelial cells from the deleterious effects of HG. Hyperglycemia-induced mitochondrial adaptation is a plausible contributor to the mechanism responsible for the delayed onset of DR; loss of hyperglycemia-induced mitochondrial adaptation may set the stage for the development of DR.
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Affiliation(s)
- Anara Serikbaeva
- Department of Physiology and Biophysics, University of Illinois at Chicago, Chicago, Illinois
| | - Yueru Li
- Department of Ophthalmology and Visual Sciences, University of Illinois at Chicago, Chicago, Illinois
| | - Balaji Ganesh
- Research Resources Center, University of Illinois at Chicago, Chicago, Illinois
| | - Ruth Zelkha
- Department of Ophthalmology and Visual Sciences, University of Illinois at Chicago, Chicago, Illinois
| | - Andrius Kazlauskas
- Department of Physiology and Biophysics, University of Illinois at Chicago, Chicago, Illinois; Department of Ophthalmology and Visual Sciences, University of Illinois at Chicago, Chicago, Illinois.
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Meng F, Guo B, Ma YQ, Li KW, Niu FJ. Puerarin: A review of its mechanisms of action and clinical studies in ophthalmology. PHYTOMEDICINE : INTERNATIONAL JOURNAL OF PHYTOTHERAPY AND PHYTOPHARMACOLOGY 2022; 107:154465. [PMID: 36166943 DOI: 10.1016/j.phymed.2022.154465] [Citation(s) in RCA: 16] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/27/2022] [Revised: 09/07/2022] [Accepted: 09/18/2022] [Indexed: 06/16/2023]
Abstract
BACKGROUND Pueraria is the common name of the dried root of either Pueraria montana var. lobata (Willd.) Maesen & S.M.Almeida ex Sanjappa & Predeep (syn. Pueraria lobata (Willd.) Ohwi) or Pueraria montana var. thomsonii (Benth.) M.R.Almeida (syn. Pueraria thomsonii Benth.). Puerarin is a C-glucoside of the isoflavone daidzein extracted from Pueraria. It has been widely investigated to explore its therapeutic role in eye diseases and the molecular mechanisms. PURPOSE To collect the available literature from 2000 to 2022 on puerarin in the treatment of ocular diseases and suggest the future required directions to improve its medicinal value. METHOD The content of this review was obtained from databases such as Web of Science, PubMed, Google Scholar, China National Knowledge Infrastructure (CNKI), and the Wanfang Database. RESULTS The search yielded 428 articles, of which 159 articles were included after excluding duplicate articles and articles related to puerarin but less relevant to the topic of the review. In eleven articles, the bioavailability of puerarin was discussed. Despite puerarin possesses diverse biological activities, its bioavailability on its own is poor. There are 95 articles in which the therapeutic mechanisms of puerarin in ocular diseases was reported. Of these, 54 articles discussed the various signalling pathways related to occular diseases affected by puerarin. The other 41 articles discussed specific biological activities of puerarin. It plays a therapeutic role in ophthalmopathy via regulating nuclear factor kappa-B (NF-ĸB), mitogen-activated protein kinases (MAPKs), PI3K/AKT, JAK/STAT, protein kinase C (PKC) and other related pathways, affecting the expression of tumour necrosis factor α (TNF-α), interleukin-1β (IL-1β), intercellular adhesion molecule-1 (ICAM-1), monocyte chemoattractant protein-1 (MCP-1), superoxide dismutase (SOD), B-cell lymphoma-2 (Bcl-2) and other cytokines resulting in anti-inflammatory, antioxidant and anti-apoptotic effects. The clinical applications of puerarin in ophthalmology were discussed in 25 articles. Eleven articles discussed the toxicity of puerarin. The literature suggests that puerarin has a good curative effect and can be used safely in clinical practice. CONCLUSION This review has illustrated the diverse applications of puerarin acting on ocular diseases and suggested that puerarin can be used for treating diabetic retinopathy, retinal vascular occlusion, glaucoma and other ocular diseases in the clinic. Some ocular diseases are the result of the combined action of multiple factors, and the effect of puerarin on different factors needs to be further studied to improve a more complete mechanism of action of puerarin. In addition, it is necessary to increase the number of subjects in clinical trials and conduct clinical trials for other ocular diseases. The information presented here will guide future research studies.
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Affiliation(s)
- Fan Meng
- Shandong University of Traditional Chinese Medicine, Daxue Road 4655, Ji'nan 250355, China
| | - Bin Guo
- Shandong University of Traditional Chinese Medicine, Daxue Road 4655, Ji'nan 250355, China
| | - Yi-Qing Ma
- Shandong University of Traditional Chinese Medicine, Daxue Road 4655, Ji'nan 250355, China
| | - Kun-Wei Li
- Shandong University of Traditional Chinese Medicine, Daxue Road 4655, Ji'nan 250355, China.
| | - Feng-Ju Niu
- Shandong University of Traditional Chinese Medicine, Daxue Road 4655, Ji'nan 250355, China.
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Wang M, Sheng KJ, Fang JC, Zhao H, Lu SM, Liu ZY, Chen BT. Redox signaling in diabetic retinopathy and opportunity for therapeutic intervention through natural products. Eur J Med Chem 2022; 244:114829. [DOI: 10.1016/j.ejmech.2022.114829] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2022] [Revised: 09/14/2022] [Accepted: 10/01/2022] [Indexed: 11/28/2022]
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Cai C, Meng C, He S, Gu C, Lhamo T, Draga D, Luo D, Qiu Q. DNA methylation in diabetic retinopathy: pathogenetic role and potential therapeutic targets. Cell Biosci 2022; 12:186. [DOI: 10.1186/s13578-022-00927-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2022] [Accepted: 11/07/2022] [Indexed: 11/18/2022] Open
Abstract
Abstract
Background
Diabetic retinopathy (DR), a specific neuron-vascular complication of diabetes, is a major cause of vision loss among middle-aged people worldwide, and the number of DR patients will increase with the increasing incidence of diabetes. At present, it is limited in difficult detection in the early stages, limited treatment and unsatisfactory treatment effects in the advanced stages.
Main body
The pathogenesis of DR is complicated and involves epigenetic modifications, oxidative stress, inflammation and neovascularization. These factors influence each other and jointly promote the development of DR. DNA methylation is the most studied epigenetic modification, which has been a key role in the regulation of gene expression and the occurrence and development of DR. Thus, this review investigates the relationship between DNA methylation and other complex pathological processes in the development of DR. From the perspective of DNA methylation, this review provides basic insights into potential biomarkers for diagnosis, preventable risk factors, and novel targets for treatment.
Conclusion
DNA methylation plays an indispensable role in DR and may serve as a prospective biomarker of this blinding disease in its relatively early stages. In combination with inhibitors of DNA methyltransferases can be a potential approach to delay or even prevent patients from getting advanced stages of DR.
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Wu Y, Zou H. Research Progress on Mitochondrial Dysfunction in Diabetic Retinopathy. Antioxidants (Basel) 2022; 11:2250. [PMID: 36421435 PMCID: PMC9686704 DOI: 10.3390/antiox11112250] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2022] [Revised: 11/07/2022] [Accepted: 11/12/2022] [Indexed: 09/07/2023] Open
Abstract
Diabetic Retinopathy (DR) is one of the most important microvascular complications of diabetes mellitus, which can lead to blindness in severe cases. Mitochondria are energy-producing organelles in eukaryotic cells, which participate in metabolism and signal transduction, and regulate cell growth, differentiation, aging, and death. Metabolic changes of retinal cells and epigenetic changes of mitochondria-related genes under high glucose can lead to mitochondrial dysfunction and induce mitochondrial pathway apoptosis. In addition, mitophagy and mitochondrial dynamics also change adaptively. These mechanisms may be related to the occurrence and progression of DR, and also provide valuable clues for the prevention and treatment of DR. This article reviews the mechanism of DR induced by mitochondrial dysfunction, and the prospects for related treatment.
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Affiliation(s)
- Yiwei Wu
- Shanghai Jiao Tong University School of Medicine, Shanghai 200025, China
| | - Haidong Zou
- Department of Ophthalmology, Shanghai General Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 200080, China
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Regulation of serine palmitoyl-transferase and Rac1-Nox2 signaling in diabetic retinopathy. Sci Rep 2022; 12:16740. [PMID: 36202842 PMCID: PMC9537524 DOI: 10.1038/s41598-022-20243-2] [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: 04/29/2022] [Accepted: 09/12/2022] [Indexed: 11/23/2022] Open
Abstract
Hyperlipidemia is considered as one of the major systemic factors associated with the development of diabetic retinopathy, and animal models have documented that its presence in a hyperglycemic environment exacerbates cytosolic ROS production (via activation of the Rac1–Nox2 axis) and mitochondrial damage. Hyperglycemia also accelerates Rac1 transcription via dynamic DNA methylation–hydroxymethylation of its promoter. In diabetes, ceramide metabolism in the retina is impaired and its accumulation is increased. Our aim was to investigate the effect of inhibition of the rate limiting enzyme of the de novo ceramide biosynthesis, serine palmitoyl-transferase (SPT), on Rac1 activation in diabetic retinopathy. Using human retinal endothelial cells, transfected with SPT-siRNA, and incubated in 20 mM d-glucose in the presence or absence of 50 µM palmitate (glucolipotoxic and glucotoxic, respectively), activities of Rac1 and Nox2, and ROS levels were quantified. For Rac1 transcriptional activation, 5 hydroxymethyl cytosine (5hmC) levels at its promoter were quantified. Key parameters were confirmed in retinal microvessels from streptozotocin-induced diabetic mice on a normal diet (type 1 diabetic model) or on a high-fat diet (45% kcal, type 2 diabetic model), injected intravitreally with SPT-siRNA. Compared to normal glucose, cells in high glucose, with or without palmitic acid, had increased Rac1–Nox2–ROS signaling, Rac1 transcripts and 5hmC levels at its promoter. Inhibition of SPT by SPT-siRNA or myriocin prevented glucotoxic- and glucolipotoxic-induced increase in Rac1–Nox2–ROS signaling and 5hmC at the Rac1 promoter. Similarly, in both type 1 and type 2 diabetic mouse models, SPT-siRNA attenuated the increase in the Rac1–Nox2–ROS axis and 5hmC at the Rac1 promoter. Thus, inhibition of the rate limiting enzyme of ceramide de novo biosynthesis, SPT, regulates activation of DNA methylation–hydroxymethylation machinery and prevents increased Rac1 transcription. This ameliorates the activation of Rac1–Nox2 signaling and protects the mitochondria from damaging cytosolic ROS, which prevents accelerated capillary cell loss. These results further raise the importance of regulating lipid levels in diabetic patients with dyslipidemia.
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