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Genetics of Diabetic Retinopathy, a Leading Cause of Irreversible Blindness in the Industrialized World. Genes (Basel) 2021; 12:genes12081200. [PMID: 34440374 PMCID: PMC8394456 DOI: 10.3390/genes12081200] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2021] [Revised: 05/29/2021] [Accepted: 07/29/2021] [Indexed: 12/14/2022] Open
Abstract
Diabetic retinopathy (DR) is a chronic complication of diabetes and a leading cause of blindness in the industrialized world. Traditional risk factors, such as glycemic control and duration of diabetes, are unable to explain why some individuals remain protected while others progress to a more severe form of the disease. Differences are also observed in DR heritability as well as the response to anti-vascular endothelial growth factor (VEGF) treatment. This review discusses various aspects of genetics in DR to shed light on DR pathogenesis and treatment. First, we discuss the global burden of DR followed by a discussion on disease pathogenesis as well as the role genetics plays in the prevalence and progression of DR. Subsequently, we provide a review of studies related to DR’s genetic contribution, such as candidate gene studies, linkage studies, and genome-wide association studies (GWAS) as well as other clinical and meta-analysis studies that have identified putative candidate genes. With the advent of newer cutting-edge technologies, identifying the genetic components in DR has played an important role in understanding DR incidence, progression, and response to treatment, thereby developing newer therapeutic targets and therapies.
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Li W, Chen S, Mei Z, Zhao F, Xiang Y. Polymorphisms in Sorbitol-Aldose Reductase (Polyol) Pathway Genes and Their Influence on Risk of Diabetic Retinopathy Among Han Chinese. Med Sci Monit 2019; 25:7073-7078. [PMID: 31539366 PMCID: PMC6767949 DOI: 10.12659/msm.917011] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
BACKGROUND Sorbitol-aldose reductase (polyol) pathway genes have been strongly linked to diabetic retinopathy. Polymorphisms in these genes may affect their functions and influence the risk of retinopathy. In this work, we investigated the influence of the rs759853 polymorphism of ALR2 gene and rs2055858 and rs3759890 polymorphisms of SDH gene on risk of diabetic retinopathy among Han Chinese. MATERIAL AND METHODS We included 3,000 subjects in our study, of which 1,500 were patients with diabetic retinopathy and 1,500 were controls without the said condition. Among the cases, 750 had the non-proliferative diabetic retinopathy (NPDR) and 750 had proliferative diabetic retinopathy (PDR). The polymorphisms were genotyped using established methods and logistic regression analysis was used to determine whether the polymorphisms were associated with risk of diabetic retinopathy. RESULTS We found that variants of ALR2 rs759853 polymorphism were significantly associated with an increased risk of diabetic retinopathy, whereas variants of SDH rs2055858 polymorphism were significantly associated with a lower risk. For the former, an odds ratio (OR) of 1.46 were noted for the heterozygous genotype (95% CI=1.25-1.70, P<0.01) and the homozygous variant genotype (OR=1.90, 95% CI=1.40-2.60, P<0.01). For SDH rs2055858 polymorphism, an OR of 0.51 (95% CI=0.43-0.61, P<0.01) and 0.34 (95% CI=0.28-0.42, P<0.01) was observed for heterozygous and homozygous variant genotype respectively. Subgroup analysis based on NPDR and PDR showed a similar finding as the combined results. CONCLUSIONS ALR2 rs759853 and SDH rs2055858 polymorphisms were respectively associated with a higher and lower risk of diabetic retinopathy.
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Affiliation(s)
- Wenliang Li
- Department of Ophthalmology, Central Hospital of Wuhan, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, China (mainland)
| | - Sisi Chen
- Department of Ophthalmology, Central Hospital of Wuhan, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, China (mainland)
| | - Zhongming Mei
- Department of Ophthalmology, Central Hospital of Wuhan, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, China (mainland)
| | - Fang Zhao
- Department of Ophthalmology, Central Hospital of Wuhan, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, China (mainland)
| | - Yi Xiang
- Department of Ophthalmology, Central Hospital of Wuhan, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, China (mainland)
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Huang Q, Liu Q, Ouyang D. Sorbinil, an Aldose Reductase Inhibitor, in Fighting Against Diabetic Complications. Med Chem 2019; 15:3-7. [PMID: 29792152 DOI: 10.2174/1573406414666180524082445] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2017] [Revised: 04/17/2018] [Accepted: 04/30/2018] [Indexed: 11/22/2022]
Abstract
BACKGROUND Aldose reductase (AR) is involved in the pathogenesis of diabetes, which is one of the major threats to global public health. OBJECTIVE In this review article, we have discussed the role of sorbinil, an AR inhibitor (ARI), in preventing diabetic complications. RESULTS AR contributes in diabetes by generating excess intracellular superoxide and other mediators of oxidative stress through polyol pathway. Inhibition of AR activity thus might be a potential approach for the management of diabetic complications. Experimental evidences indicated that sorbinil can decrease AR activity and inhibit polyol pathway. Both in vitro and animal model studies reported the efficacy of sorbinil in controlling the progression of diabetes. Moreover, Sorbinil has been found to be comparatively safer than other ARIs for human use. But, it is still in earlyphase testing for the treatment of diabetic complications clinically. CONCLUSION Sorbinil is an effective ARI, which could play therapeutic role in treating diabetes and diabetic complications. However, advanced clinical trials are required for sorbinil so that it could be applied with the lowest efficacious dose in humans.
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Affiliation(s)
- Qi Huang
- Department of Clinical Pharmacology, Xiangya Hospital of Central South University, Changsha 410008, China.,Department of Pharmacy, Xiangya Hospital of Central South University, Changsha, Hunan 410008, China
| | - Qiong Liu
- Department of Oncology, Xiangya Hospital of Central South University, Changsha, Hunan 410008, China
| | - Dongsheng Ouyang
- Department of Clinical Pharmacology, Xiangya Hospital of Central South University, Changsha 410008, China
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Wihandani DM, Suastika K, Agus Bagiada IN, Malik SG. Polymorphisms of Aldose Reductase (ALR2) Regulatory Gene are Risk Factors for Diabetic Retinopathy in Type-2 Diabetes Mellitus Patients in Bali, Indonesia. Open Ophthalmol J 2018; 12:281-288. [PMID: 30450144 PMCID: PMC6198411 DOI: 10.2174/1874364101812010281] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2018] [Revised: 08/13/2018] [Accepted: 09/12/2018] [Indexed: 11/22/2022] Open
Abstract
Aim The study aimed to elucidate whether the polymorphisms of the aldose reductase regulatory gene were risk factors for Diabetic Retinopathy (DR) in type-2 diabetes mellitus (T2DM) patients in Bali. Methods This is a case-control study including 35 cases of T2DM patients with DR paired with 35 cases with non-DR as controls. PCR analysis and DNA-sequencing were carried out to detect the C(-106)T and C(-12)G polymorphisms at the regulatory region of Aldose Reductase (ALR2) gene. Genotype and allele distributions were analyzed by Chi-squared test and independent t-and Mann-Whitney U tests were used to analyze other data. Results Among all subjects in both groups, the baseline characteristics were homogenous except for systolic blood pressure, fasting blood glucose and 2-hours post-prandial blood glucose. This study found two polymorphisms, C(-104)T and C(-9)G, in the regulatory region of ALR2 gene. The result showed that the C(-104)T polymorphism was a risk factor for DR (OR=36; 95% CI = 4.43-292.85; p=0.001), but not the C(-9)G polymorphism (OR=1.28; 95% CI=0.48-3.38; p=0.621). Other findings in the study revealed that CC/CC haplotype is a protective factor for DR (OR=0.198; p=0.002), whereas CT/CC and CT/CG haplotypes as risk factors for DR with OR=15.58; p=0.002 and OR=2.29; p=0.005 respectively. Conclusion It can be concluded that C(-104)T polymorphism in the regulatory region of Aldose Reductase (ALR2) gene was the risk factor for DR among T2DM patients in Bali, Indonesia. However, small sample size, systolic blood pressure, fasting blood glucose and 2-hours post-prandial blood glucose could affect our finding.
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Affiliation(s)
- Desak Made Wihandani
- Department of Biochemistry, Faculty of Medicine, Udayana University, Jl. PB Sudirman, Denpasar 80232, Bali, Indonesia
| | - Ketut Suastika
- Division of Endocrinology and Metabolism, Department of Internal Medicine, Faculty of Medicine, Udayana University, Jl. PB Sudirman, and Sanglah Hospital, Jl. Kesehatan, Denpasar, Bali, Indonesia
| | - I Nyoman Agus Bagiada
- Department of Biochemistry, Faculty of Medicine, Udayana University, Jl. PB Sudirman, Denpasar 80232, Bali, Indonesia
| | - Safarina G Malik
- Eijkman Institute for Molecular Biology, Jl. Diponegoro 69, Jakarta 10430, Indonesia
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Wang Y, Yu M, Mo L, Li Z, Wang J, Zhou HH, Ouyang DS. Aldose reductase C-106T polymorphism is associated with the risk of essential hypertension. Gene 2016; 591:65-68. [DOI: 10.1016/j.gene.2016.06.043] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2016] [Revised: 06/07/2016] [Accepted: 06/21/2016] [Indexed: 01/28/2023]
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Aldose reductase, ocular diabetic complications and the development of topical Kinostat®. Prog Retin Eye Res 2016; 54:1-29. [DOI: 10.1016/j.preteyeres.2016.04.006] [Citation(s) in RCA: 44] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2016] [Revised: 04/11/2016] [Accepted: 04/14/2016] [Indexed: 12/20/2022]
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Witzel II, Jelinek HF, Khalaf K, Lee S, Khandoker AH, Alsafar H. Identifying Common Genetic Risk Factors of Diabetic Neuropathies. Front Endocrinol (Lausanne) 2015; 6:88. [PMID: 26074879 PMCID: PMC4447004 DOI: 10.3389/fendo.2015.00088] [Citation(s) in RCA: 45] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/10/2015] [Accepted: 05/13/2015] [Indexed: 12/13/2022] Open
Abstract
Type 2 diabetes mellitus (T2DM) is a global public health problem of epidemic proportions, with 60-70% of affected individuals suffering from associated neurovascular complications that act on multiple organ systems. The most common and clinically significant neuropathies of T2DM include uremic neuropathy, peripheral neuropathy, and cardiac autonomic neuropathy. These conditions seriously impact an individual's quality of life and significantly increase the risk of morbidity and mortality. Although advances in gene sequencing technologies have identified several genetic variants that may regulate the development and progression of T2DM, little is known about whether or not the variants are involved in disease progression and how these genetic variants are associated with diabetic neuropathy specifically. Significant missing heritability data and complex disease etiologies remain to be explained. This article is the first to provide a review of the genetic risk variants implicated in the diabetic neuropathies and to highlight potential commonalities. We thereby aim to contribute to the creation of a genetic-metabolic model that will help to elucidate the cause of diabetic neuropathies, evaluate a patient's risk profile, and ultimately facilitate preventative and targeted treatment for the individual.
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Affiliation(s)
- Ini-Isabée Witzel
- Biomedical Engineering Department, Khalifa University of Science, Technology and Research, Abu Dhabi, United Arab Emirates
| | - Herbert F. Jelinek
- Australian School of Advanced Medicine, Macquarie University, Sydney, NSW, Australia
- Centre for Research in Complex Systems, School of Community Health, Charles Sturt University, Albury, NSW, Australia
| | - Kinda Khalaf
- Biomedical Engineering Department, Khalifa University of Science, Technology and Research, Abu Dhabi, United Arab Emirates
| | - Sungmun Lee
- Biomedical Engineering Department, Khalifa University of Science, Technology and Research, Abu Dhabi, United Arab Emirates
| | - Ahsan H. Khandoker
- Biomedical Engineering Department, Khalifa University of Science, Technology and Research, Abu Dhabi, United Arab Emirates
- Electrical and Electronic Engineering Department, The University of Melbourne, Parkville, VIC, Australia
| | - Habiba Alsafar
- Biomedical Engineering Department, Khalifa University of Science, Technology and Research, Abu Dhabi, United Arab Emirates
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Cui W, Du B, Cui Y, Kong L, Wu H, Wang Y, Miao L, Zhou W. Is rs759853 polymorphism in promoter of aldose reductase gene a risk factor for diabetic nephropathy? A meta-analysis. Eur J Med Res 2015; 20:14. [PMID: 25885804 PMCID: PMC4335367 DOI: 10.1186/s40001-015-0089-5] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2014] [Accepted: 01/20/2015] [Indexed: 11/28/2022] Open
Abstract
Background So far, a number of case-control or cohort studies have been carried out to investigate the relationship between rs759853 polymorphism in the promoter of aldose reductase (AR) gene and the risk of diabetic nephropathy (DN). However, the results have generated considerable controversy. We performed this study to clarify the linkage between this gene mutation and the risk of DN. Methods A comprehensive literature search of electronic databases and a well-organized meta-analysis were conducted. Results Twelve comparisons and 4,735 individuals from nine published case-control or cohort studies were included finally. From none to large heterogeneity was observed, therefore, both fixed and random models were used. Significant differences were found between AR rs759853 polymorphism and susceptibility of DN from both type 1 and type 2 diabetes in all genetic models (allele contrast, OR = 1.37, CI (1.18, 1.59), P < 0.0001; additive model, OR = 1.78, CI (1.25, 2.53), P = 0.01; recessive model OR = 1.33 CI (1.08, 1.63), P = 0.008; dominant model, OR = 1.52, CI (1.26, 1.84), P < 0.0001; codominance model OR = 1.30 (1.15, 1.47), P < 0.0001). In stratified meta-analyses for type 2 diabetes by ethnicity, the significant relationship was found in allele contrast and dominant model in Caucasians, and in allele contrast and codominance model in Asians. However, data do not support the linkage between this gene mutation and the progression of DN. There was no significant publication bias. Conclusions The evidence currently available shows that the AR rs759853 polymorphism may correlate with the susceptibility of DN. However, data do not support the association between this DNA variation and the progression of DN.
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Affiliation(s)
- Wenpeng Cui
- Department of Nephrology, Second Hospital of Jilin University, 218 Ziqiang Street, Changchun, Jilin, 130041, China.
| | - Bing Du
- Department of Cardiology, the Second Part of First Hospital, Jilin University, 3302 Jilin Road, Changchun, Jilin, 130032, China.
| | - Yingchun Cui
- Department of Nephrology, Second Hospital of Jilin University, 218 Ziqiang Street, Changchun, Jilin, 130041, China.
| | - Lili Kong
- Department of Nephrology, Second Hospital of Jilin University, 218 Ziqiang Street, Changchun, Jilin, 130041, China.
| | - Hao Wu
- Department of Nephrology, Second Hospital of Jilin University, 218 Ziqiang Street, Changchun, Jilin, 130041, China.
| | - Yangwei Wang
- Department of Nephrology, Second Hospital of Jilin University, 218 Ziqiang Street, Changchun, Jilin, 130041, China.
| | - Lining Miao
- Department of Nephrology, Second Hospital of Jilin University, 218 Ziqiang Street, Changchun, Jilin, 130041, China.
| | - Wenhua Zhou
- Department of Nephrology, Second Hospital of Jilin University, 218 Ziqiang Street, Changchun, Jilin, 130041, China.
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Rezaee MRS, Amiri AA, Hashemi-Soteh MB, Daneshvar F, Emady-Jamaly R, Jafari R, Soleimani B, Haghiaminjan H. Aldose reductase C-106T gene polymorphism in type 2 diabetics with microangiopathy in Iranian individuals. Indian J Endocrinol Metab 2015; 19:95-99. [PMID: 25593834 PMCID: PMC4287789 DOI: 10.4103/2230-8210.131762] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/18/2023] Open
Abstract
BACKGROUND Aldose reductase (AR) is the rate-limiting enzyme in the glucose metabolism, which has been implicated in the pathogenesis of diabetic microvascular complications (MVCs). Frequent C-106T polymorphism in the promoter of the AR gene may change the expression of the gene. AIMS The aim of the following study is to study the association between AR C106T genotypes and diabetic MVCs in Iranian population. MATERIALS AND METHODS We included 206 type 2 diabetic patients categorized into two groups according to the presence or absence of diabetic microangiopathy. The cases of interest were diabetic neuropathy, retinopathy and nephropathy identified during clinical and or laboratory examination. In addition, 114 age- and sex-matched individuals were selected to serve as a control group. AR genotyping was done using an amplification gel electrophoresis. RESULTS The frequency of CC genotype was specifically higher in subjects with diabetic retinopathy as compared to those without it (53.2% vs. 38.1%, P = 0.030). Patients with diabetic microangiopathy in general; however, did not differ significantly between AR genotype groups. CONCLUSION The C-106T polymorphism in the AR gene is likely a risk factor for development of only retinal complication of diabetes microvascular in Iranian individuals.
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Affiliation(s)
- Majid Reza Sheikh Rezaee
- Bu Ali-Sina Clinical Research Development Unit, Mazandaran University of Medical Sciences, Mazandaran, Sari, Iran
| | - Ahmad Ahmadzadeh Amiri
- Bu Ali-Sina Clinical Research Development Unit, Mazandaran University of Medical Sciences, Mazandaran, Sari, Iran
| | - Mohammad Bagher Hashemi-Soteh
- Molecular and Cell Biology Research Center and Medical Faculty, Mazandaran University of Medical Sciences, Mazandaran, Sari, Iran
| | | | | | - Reza Jafari
- Bu Ali-Sina Clinical Research Development Unit, Mazandaran University of Medical Sciences, Mazandaran, Sari, Iran
| | - Behyar Soleimani
- Bu Ali-Sina Clinical Research Development Unit, Mazandaran University of Medical Sciences, Mazandaran, Sari, Iran
| | - Hamed Haghiaminjan
- Department of Toxicology and Pharmacology, Tehran University of Medical Sciences, Tehran, Iran
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Murea M, Ma L, Freedman BI. Genetic and environmental factors associated with type 2 diabetes and diabetic vascular complications. Rev Diabet Stud 2012; 9:6-22. [PMID: 22972441 DOI: 10.1900/rds.2012.9.6] [Citation(s) in RCA: 216] [Impact Index Per Article: 18.0] [Reference Citation Analysis] [Abstract] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Faced with a global epidemic of type 2 diabetes (T2D), it is critical that researchers improve our understanding of the pathogenesis of T2D and related vascular complications. These findings may ultimately lead to novel treatment options for disease prevention or delaying progression. Two major paradigms jointly underlie the development of T2D and related coronary artery disease, diabetic nephropathy, and diabetic retinopathy. These paradigms include the genetic risk variants and behavioral/environmental factors. This article systematically reviews the literature supporting genetic determinants in the pathogenesis of T2D and diabetic vasculopathy, and the functional implications of these gene variants on the regulation of beta-cell function and glucose homeostasis. We update the discovery of diabetes and diabetic vasculopathy risk variants, and describe the genetic technologies that have uncovered them. Also, genomic linkage between obesity and T2D is discussed. There is a complementary role for behavioral and environmental factors modulating the genetic susceptibility and diabetes risk. Epidemiological and clinical data demonstrating the effects of behavioral and novel environmental exposures on disease expression are reviewed. Finally, a succinct overview of recent landmark clinical trials addressing glycemic control and its impact on rates of vascular complications is presented. It is expected that novel strategies to exploit the gene- and exposure-related underpinnings of T2D will soon result.
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Affiliation(s)
- Mariana Murea
- Department of Internal Medicine, Section on Nephrology, Wake Forest School of Medicine, Winston-Salem, North Carolina, USA.
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Wu JC, Li XH, Wang JB, Tang JF, Wang YF, Peng YD. Glyoxalase I and Aldose Reductase Gene Polymorphisms and Susceptibility to Carotid Atherosclerosis in Type 2 Diabetes. Genet Test Mol Biomarkers 2011; 15:273-9. [PMID: 21294693 DOI: 10.1089/gtmb.2010.0075] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Affiliation(s)
- Jing-cheng Wu
- Department of Endocrinology and Metabolism, Shanghai Jiao Tong University Affiliated First People's Hospital, Shanghai, P.R. China
| | - Xiao-hua Li
- Department of Endocrinology and Metabolism, Shanghai Jiao Tong University Affiliated First People's Hospital, Shanghai, P.R. China
| | - Jian-bo Wang
- Department of Endocrinology and Metabolism, Shanghai Jiao Tong University Affiliated First People's Hospital, Shanghai, P.R. China
| | - Jian-feng Tang
- Department of Endocrinology and Metabolism, Shanghai Jiao Tong University Affiliated First People's Hospital, Shanghai, P.R. China
| | - Yu-fei Wang
- Department of Endocrinology and Metabolism, Shanghai Jiao Tong University Affiliated First People's Hospital, Shanghai, P.R. China
| | - Yong-de Peng
- Department of Endocrinology and Metabolism, Shanghai Jiao Tong University Affiliated First People's Hospital, Shanghai, P.R. China
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Zablocki GJ, Ruzycki PA, Overturf MA, Palla S, Reddy GB, Petrash JM. Aldose reductase-mediated induction of epithelium-to-mesenchymal transition (EMT) in lens. Chem Biol Interact 2011; 191:351-6. [PMID: 21329682 DOI: 10.1016/j.cbi.2011.02.005] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2010] [Revised: 02/01/2011] [Accepted: 02/01/2011] [Indexed: 12/14/2022]
Abstract
Cataract is a key factor in the morbidity associated with diabetes. While the pathogenesis of diabetic cataract formation is poorly understood, previous research has identified aldose reductase (ALR2) as a key player. To elucidate a potential role for this enzyme in diabetic cataract formation, we created a series of transgenic mice designed for expression of human ALR2 (AKR1B1) in epithelial and outer cortical fiber cells of the lens. One of the founder lines, designated PAR39, developed an early onset cataract that involved formation of a plaque of cells at the anterior aspect of the lens. These cells appear to separate from the anterior epithelium and undergo a dramatic change that is reminiscent of the epithelial to mesenchymal transition (EMT). We characterized this phenotype in the PAR39 strain by examining rates of cell proliferation and by immunostaining for markers of EMT. Incorporation of the thymidine analog bromodeoxyuridine (BrdU) was used to estimate cell proliferation in two functional areas of the lens epithelium: the mitotically active germinative zone (GZ) and the less proliferative center zone (CZ). Staining cell nuclei with diamido 4',6-diamidino-2-phenylindole (DAPI) was used to establish a total cell count in the demarcated areas. Lens epithelium in PAR39 transgenic mice demonstrated a decrease in the percentage of BrdU/DAPI staining within the GZ as compared to nontransgenic littermate controls (8.1% vs. 10.9%). A similar decrease in BrdU/DAPI was observed in the CZ (0.6% compared to 3.3%). However, cell density was greater within the GZ of PAR39 mice as compared with nontransgenic controls, while it was not significantly different in the CZ among the two groups. Furthermore, cells associated with the epithelial plaque did not stain positive for BrdU, but were strongly positive for alpha-smooth muscle actin, a classical marker for EMT. These findings suggest that ALR2 over-expression is associated with an alteration in the balance between proliferation and apoptosis of epithelial cells in the mouse lens, and that cells associated with epithelial plaques in the PAR39 lens have features in common with cells undergoing EMT.
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Affiliation(s)
- Gregory J Zablocki
- Department of Ophthalmology, University of Colorado School of Medicine, Aurora, CO 80045, United States
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Uthra S, Raman R, Mukesh BN, Rajkumar SA, Kumari P, Lakshmipathy P, Gnanamoorthy P, Sharma T, McCarty CA, Kumaramanickavel G. Diabetic retinopathy: Validation study of ALR2, RAGE, iNOS and TNFB gene variants in a south Indian cohort. Ophthalmic Genet 2011; 31:244-51. [PMID: 21067489 DOI: 10.3109/13816810.2010.523037] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
PURPOSE We previously reported the association of the Z-2 allele of the promoter dinucleotide repeat in the Aldose reductase (ALR2) gene, the (CCTTT)₁₅ allele in the promoter of inductible nitric oxide synthase (iNOS) gene, and the (GT)₁₃ promoter polymorphism in the tumor necrosis factor β (TNFB) gene with an increased risk for diabetic retinopathy (DR), and the Gly82Ser polymorphism in the receptor for advanced glycation end products (RAGE) gene and the (GT)₉ allele of the TNFB gene with low-risk for DR in a hospital-based self-reported type 2 diabetes mellitus (T2DM) patients. We have repeated the study in a population-based south Indian cohort to validate the same variations in these genes. MATERIALS AND METHODS Type 2 diabetic patients with and without retinopathy (DR+ and DR- respectively) were recruited. (CA)(n) repeat, Gly82Ser, (CCTTT)(n) repeat and (GT)(n) repeat in ALR2, RAGE, iNOS and TNFB genes respectively were genotyped and their frequencies were analyzed using the relevant statistical tests. RESULTS Different allelic associations were observed in the present study as compared to our previous reports. Z+2 allele of ALR2, 13-repeat genotype of iNOS, 15-repeat genotype of TNF-β, genes were associated with susceptibility to DR. Gly82Ser polymorphisms of the RAGE gene were not associated with DR in the present study. CONCLUSION The present data show a difference in the association of variations in ALR2, iNOS and TNFB genes with DR, when compared to our previous reports; this could be attributed to differences between the study populations of the past and present report.
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Affiliation(s)
- Satagopan Uthra
- SN ONGC Department of Genetics and Molecular Biology, Medical and Vision Research Foundations, Sankara Nethralaya, Chennai, India.
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Zhang H, Tasaka S, Shiraishi Y, Fukunaga K, Yamada W, Seki H, Ogawa Y, Miyamoto K, Nakano Y, Hasegawa N, Miyasho T, Maruyama I, Ishizaka A. Role of soluble receptor for advanced glycation end products on endotoxin-induced lung injury. Am J Respir Crit Care Med 2008; 178:356-62. [PMID: 18535257 DOI: 10.1164/rccm.200707-1069oc] [Citation(s) in RCA: 104] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023] Open
Abstract
RATIONALE The interaction of receptor for advanced glycation end products (RAGE) and its ligands often leads to inflammatory processes or tissue injury, although the effect of the blockade of RAGE signaling on lung injury remains to be investigated. OBJECTIVES Using a murine model of lung injury induced by intratracheal lipopolysaccharide (LPS), we evaluated RAGE expression in the airspace and the effect of recombinant soluble RAGE (sRAGE) on LPS-induced lung injury. METHODS First, the expression of sRAGE in bronchoalveolar lavage (BAL) fluid was determined at 24 hours after intratracheal instillation of LPS or phosphate-buffered saline. Next, to evaluate the effect of sRAGE, BAL fluid was collected for cell counting and measurements of lung permeability and cytokine concentrations 24 hours after intratracheal LPS in the mice with or without intraperitoneal administration of sRAGE 1 hour after the instillation. In another series, lungs were sampled for histopathology and detection of apoptotic cells. The activation of nuclear factor (NF)-kappaB was analyzed 4 hours after LPS instillation. MEASUREMENTS AND MAIN RESULTS In response to LPS challenge, a RAGE isoform of 48 kD was detected in the BAL fluid. Treatment with sRAGE significantly attenuated the increases in neutrophil infiltration, lung permeability, production of inflammatory cytokines, NF-kappaB activation, and apoptotic cells in the lung as well as development of pathologic changes after LPS instillation. CONCLUSIONS RAGE plays an important role in the pathogenesis of LPS-induced lung injury in mice. It was suggested that sRAGE should be tested as a treatment modality in other models of acute lung injury.
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Affiliation(s)
- Haiying Zhang
- Division of Pulmonary Medicine, Keio University School of Medicine, Tokyo, Japan
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16
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Thamotharampillai K, Chan AKF, Bennetts B, Craig ME, Cusumano J, Silink M, Oates PJ, Donaghue KC. Decline in neurophysiological function after 7 years in an adolescent diabetic cohort and the role of aldose reductase gene polymorphisms. Diabetes Care 2006; 29:2053-7. [PMID: 16936152 DOI: 10.2337/dc06-0678] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
OBJECTIVE This 7-year longitudinal study examines the potential impact of aldose reductase gene (AKR1B1) polymorphisms on the decline of nerve function in an adolescent diabetic cohort. RESEARCH DESIGN AND METHODS Patients with type 1 diabetes (n = 262) were assessed with three cardiovascular autonomic tests (heart rate variation during deep breathing, Valsalva maneuver, and during standing from a lying position) and pupillometry (resting pupil diameter, constriction velocity, and reflex amplitude), thermal, and vibration thresholds on the foot. Genotyping was performed for promoters (C-106T and C-12G), (CA)(n) dinucleotide repeats, and intragenic BamH1 polymorphism. RESULTS Median time between first and last assessment was 7.0 years (interquartile range 5.1-11.1), with a median of five assessments (four to seven) per individual. At first assessment, median age was 12.7 years (11.7-13.9), median duration was 5.3 years (3.4-8.0), and median HbA(1c) was 8.5% (7.8-9.3). All tests declined over time except for two cardiovascular autonomic tests and vibration discrimination. Faster decline in maximum constriction velocity was found to associate with the Z-2 allele (P = 0.045), Z-2/Z-2 (P = 0.026). Slower decline in hot thermal threshold discrimination associated with Z+2 (P = 0.044), Z+2/Z+2 (P < 0.0005), Z+2/T (P = 0.038), and bb (P = 0.0001). CONCLUSIONS Most autonomic and quantitative sensory nerve testings declined over time. AKR1B1 polymorphisms were strongly associated with the rate of decline of these complications.
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Affiliation(s)
- Keerthi Thamotharampillai
- Institute of Endocrinology and Diabetes, The Children's Hospital at Westmead, Westmead, NSW 2145, Australia
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17
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Watarai A, Nakashima E, Hamada Y, Watanabe G, Naruse K, Miwa K, Kobayashi Y, Kamiya H, Nakae M, Hamajima N, Sekido Y, Niwa T, Oiso Y, Nakamura J. Aldose reductase gene is associated with diabetic macroangiopathy in Japanese Type 2 diabetic patients. Diabet Med 2006; 23:894-9. [PMID: 16911628 PMCID: PMC1619898 DOI: 10.1111/j.1464-5491.2006.01946.x] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
AIMS The aldose reductase (AR) gene, a rate-limiting enzyme of the polyol pathway, has been investigated as a candidate gene in determining susceptibility to diabetic microangiopathy. However, the association of the AR gene with diabetic macroangiopathy has not been investigated. Therefore, the present study was conducted to determine whether genetic variations of AR may determine susceptibility to diabetic macroangiopathy. METHODS There were 378 Type 2 diabetic patients enrolled in this study. A single nucleotide polymorphism in the promoter region (C-106T) was genotyped and the AR protein content of erythrocytes measured by ELISA. RESULTS There were no significant differences in genotypic or allelic distribution in patients with or without ischaemic heart diseases, but there was a significant increase in the frequency of the CT + TT genotype and T allele in patients with stroke (P = 0.019 and P = 0.012). The erythrocyte AR protein content was increased in patients with the CT and TT genotype compared with those with the CC genotype. After adjustment for age, duration of diabetes, body mass index, systolic blood pressure, HbA1c, and serum creatinine, triglycerides, and total cholesterol in multivariate logistic-regression models, the association between this AR genotype and stroke remained significant. CONCLUSIONS Our results suggest that the CT or TT genotype of the AR gene might be a genetic marker of susceptibility to stroke in Type 2 diabetic patients. This observation might contribute to the development of strategies for the prevention of stroke in Type 2 diabetic patients.
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Affiliation(s)
- A Watarai
- Department of Endocrinology and Diabetes, Nagoya University Graduate School of Medicine, Nagoya, Japan
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18
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dos Santos KG, Canani LH, Gross JL, Tschiedel B, Souto KEP, Roisenberg I. The -106CC genotype of the aldose reductase gene is associated with an increased risk of proliferative diabetic retinopathy in Caucasian-Brazilians with type 2 diabetes. Mol Genet Metab 2006; 88:280-4. [PMID: 16545977 DOI: 10.1016/j.ymgme.2006.02.002] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/05/2005] [Revised: 01/30/2006] [Accepted: 02/01/2006] [Indexed: 10/24/2022]
Abstract
Diabetic retinopathy is a sight-threatening chronic complication of diabetes mellitus and is the leading cause of acquired blindness in adults. The -106C>T polymorphism in the promoter region of the aldose reductase (AR) gene has been shown to be associated with the susceptibility to diabetic nephropathy in type 2 diabetes, but the findings regarding the occurrence of diabetic retinopathy are conflicting. In this case-control study, we investigated whether the -106C>T polymorphism in the AR gene is involved in the development and progression of diabetic retinopathy in 579 Brazilians with type 2 diabetes (424 Caucasian- and 155 African-Brazilians). Patients underwent a clinical and laboratory evaluation consisting of a questionnaire, physical examination, assessment of diabetic complications and laboratory tests. Genotype analysis was performed using the polymerase chain reaction followed by digestion with restriction enzyme. Logistic regression analysis was used to control for independent risk factors associated with diabetic retinopathy. There were no differences in either genotype or allele frequencies for the -106C>T polymorphism between type 2 diabetic patients with or without diabetic retinopathy, in both ethnic groups. However, the CC genotype was associated with an increased risk of having proliferative diabetic retinopathy in Caucasian-Brazilians with type 2 diabetes (odds ratio (OR)=2.04; 95% confidence interval (CI)=1.21-3.45; P=0.007), independently of other risk factors associated with this complication. Thus, our results show that the -106CC genotype (-106C>T polymorphism) in the AR gene is related to the progression of diabetic retinopathy in Caucasian-Brazilians with type 2 diabetes.
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19
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Yang B, Hodgkinson AD, Oates PJ, Kwon HM, Millward BA, Demaine AG. Elevated activity of transcription factor nuclear factor of activated T-cells 5 (NFAT5) and diabetic nephropathy. Diabetes 2006; 55:1450-5. [PMID: 16644704 DOI: 10.2337/db05-1260] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Abstract
The expression of aldose reductase is tightly regulated by the transcription factor tonicity response element binding protein (TonEBP/NFAT5) binding to three osmotic response elements (OREs; OREA, OREB, and OREC) in the gene. The aim was to investigate the contribution of NFAT5 to the pathogenesis of diabetic nephropathy. Peripheral blood mononuclear cells (PBMCs) were isolated from the following subjects: 44 Caucasoid patients with type 1 diabetes, of whom 26 had nephropathy and 18 had no nephropathy after a diabetes duration of 20 years, and 13 normal healthy control subjects. In addition, human mesangial cells (HMCs) were isolated from the normal lobe of 10 kidneys following radical nephrectomy for renal cell carcinoma. Nuclear and cytoplasmic proteins were extracted from PBMCs and HMCs and cultured in either normal or high-glucose (31 mmol/l D-glucose) conditions for 5 days. NFAT5 binding activity was quantitated using electrophoretic mobility shift assays for each of the OREs. Western blotting was used to measure aldose reductase and sorbitol dehydrogenase protein levels. There were significant fold increases in DNA binding activities of NFAT5 to OREB (2.06 +/- 0.03 vs. 1.33 +/- 0.18, P = 0.033) and OREC (1.94 +/- 0.21 vs. 1.39 +/- 0.11, P = 0.024) in PBMCs from patients with diabetic nephropathy compared with diabetic control subjects cultured under high glucose. Aldose reductase and sorbitol dehydrogenase protein levels in the patients with diabetic nephropathy were significantly increased in PBMCs cultured in high-glucose conditions. In HMCs cultured under high glucose, there were significant increases in NFAT5 binding activities to OREA, OREB, and OREC by 1.38 +/- 0.22-, 1.84 +/- 0.44-, and 2.38 +/- 1.15-fold, respectively. Similar results were found in HMCs exposed to high glucose (aldose reductase 1.30 +/- 0.06-fold and sorbitol dehydrogenease 1.54 +/- 0.24-fold increases). Finally, the silencing of the NFAT5 gene in vitro reduced the expression of the aldose reductase gene. In conclusion, these results show that aldose reductase is upregulated by the transcriptional factor NFAT5 under high-glucose conditions in both PBMCs and HMCs.
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Affiliation(s)
- Bingmei Yang
- Molecular Medicine Research Group, The John Bull Building, Research Way, Peninsula Medical School, Universities of Exeter and Plymouth, Plymouth PL6 8BU, U.K
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20
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Wolford JK, Yeatts KA, Red Eagle AR, Nelson RG, Knowler WC, Hanson RL. Variants in the gene encoding aldose reductase (AKR1B1) and diabetic nephropathy in American Indians. Diabet Med 2006; 23:367-76. [PMID: 16620264 DOI: 10.1111/j.1464-5491.2006.01834.x] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
Abstract
AIMS The aldose reductase gene (AKR1B1) is a strong candidate for diabetic nephropathy, and the T allele at rs759853 and the Z-2 allele at an [AC]n microsatellite are associated with diabetic kidney disease in some populations. As AKR1B1 is located on 7q35, where we have previously reported linkage to diabetic nephropathy in Pima Indians, this study examined the association of AKR1B1 variants with diabetic nephropathy in this population. METHODS AKR1B1 variants were identified by sequencing and genotyped using allelic discrimination and pyrosequencing. Genotype distributions were compared between 107 cases with diabetic end-stage renal disease and 108 control subjects with diabetes for > or = 10 years and no evidence of nephropathy, and between 141 individuals with nephropathy and 416 individuals without heavy proteinuria in a family study of 257 sibships. RESULTS We identified 11 AKR1B1 single nucleotide polymorphisms (SNPs) and the [AC]n microsatellite polymorphism. Three SNPs were rare and two were in 100% genotypic concordance; thus, eight polymorphisms were genotyped. No variant was associated with diabetic kidney disease in the case-control or family-based study. For example, the T allele at rs759853 had an allele frequency of 0.165 in cases and 0.171 in control subjects (OR = 0.96, 95% CI, 0.57-1.59, P = 0.86); in the family study its frequency was 0.140 and 0.169 in affected and unaffected individuals, respectively (OR = 0.90, 95% CI, 0.53-1.54 P = 0.71). Corresponding values for the Z-2 allele at the [AC]n microsatellite were OR = 1.09 (95% CI 0.72-1.66, P = 0.67) and OR = 1.25 (95% CI 0.81-1.95, P = 0.31) in the case-control and family studies, respectively. CONCLUSIONS Common AKR1B1 polymorphisms are unlikely to be major determinants of diabetic nephropathy in this population.
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Affiliation(s)
- J K Wolford
- Translational Genomics Research Institute, Diabetes Research Unit, Phoenix, AZ 85004, USA.
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21
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Donaghue KC, Margan SH, Chan AKF, Holloway B, Silink M, Rangel T, Bennetts B. The association of aldose reductase gene (AKR1B1) polymorphisms with diabetic neuropathy in adolescents. Diabet Med 2005; 22:1315-20. [PMID: 16176189 DOI: 10.1111/j.1464-5491.2005.01631.x] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
AIMS Variants in the aldose reductase gene (AKR1B1) have been implicated in the development of diabetic retinopathy and nephropathy, with the most convincing data identifying a (CA)(n) repeat microsatellite allele (Z-2), which has a functional role in gene expression. In this study the association between polymorphisms in the AKR1B1 gene and diabetic neuropathy was investigated. METHODS The pupillary response to light was used as the major outcome in this study along with abnormal hot thermal threshold. Three hundred and sixty-three adolescents underwent genotyping of the AKR1B1 gene. The microsatellite (CA)(n) repeat was sequenced and two single nucleotide polymorphisms, -106C-->T and -12C-->G, were investigated by restriction fragment length polymorphism. RESULTS Seventy-six percent of participants had pupillary abnormalities (45% with two, 15% with three abnormalities). Presence of the Z-2/Z-2 genotype increased the risk nearly three-fold for pupillary abnormalities [odds ratio (OR) 3.02, 95% confidence interval (CI) 1.14, 7.98). The susceptibility genotypes (Z-2/Z-2 with -106C/-106C, Z-2/Z with -106C/-106C or Z/Z with -106C/-106C) were associated with resting pupil diameter abnormalities when compared with the protective genotypes (Z+2/Z+2 or -106T/-106T) (OR 2.83, 95% CI 1.25, 6.41). The combination of Z+2/-106T reduced the risk of abnormal heat discrimination (OR 0.48, 95% CI 0.23, 0.99). CONCLUSIONS In this study we have shown that Z-2/Z-2 genotype is significantly associated with the development of pupillary abnormality, an early indicator of diabetic autonomic neuropathy, in adolescent Australian patients with Type 1 diabetes.
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Affiliation(s)
- K C Donaghue
- Institute of Endocrinology and Diabetes, Children's Hospital at Westmead, New South Wales, Australia.
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Bierhaus A, Humpert PM, Morcos M, Wendt T, Chavakis T, Arnold B, Stern DM, Nawroth PP. Understanding RAGE, the receptor for advanced glycation end products. J Mol Med (Berl) 2005; 83:876-86. [PMID: 16133426 DOI: 10.1007/s00109-005-0688-7] [Citation(s) in RCA: 928] [Impact Index Per Article: 48.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2005] [Accepted: 05/20/2005] [Indexed: 12/11/2022]
Abstract
Advanced glycation end products (AGEs), S100/calgranulins, HMGB1-proteins, amyloid-beta peptides, and the family of beta-sheet fibrils have been shown to contribute to a number of chronic diseases such as diabetes, amyloidoses, inflammatory conditions, and tumors by promoting cellular dysfunction via binding to cellular surface receptors. The receptor for AGEs (RAGE) is a multiligand receptor of the immunoglobulin superfamily of cell surface molecules acting as counter-receptor for these diverse molecules. Engagement of RAGE converts a brief pulse of cellular activation to sustained cellular dysfunction and tissue destruction. The involvement of RAGE in pathophysiologic processes has been demonstrated in murine models of chronic disease using either a receptor decoy such as soluble RAGE (sRAGE), RAGE neutralizing antibodies, or a dominant-negative form of the receptor. Studies with RAGE-/- mice confirmed that RAGE contributes, at least in part, to the development of late diabetic complications, such as neuropathy and nephropathy, macrovascular disease, and chronic inflammation. Furthermore, deletion of RAGE provided protection from the lethal effects of septic shock caused by cecal ligation and puncture (CLP). In contrast, deletion of RAGE had no effect on the host response in delayed-type hypersensitivity (DTH). Despite the lack of effect seen in adaptive immunity by the deletion of RAGE, administration of the receptor decoy, sRAGE, still afforded a protective effect in RAGE-/- mice. Thus, sRAGE is likely to sequester ligands, thereby preventing their interaction with other receptors in addition to RAGE. These data suggest that, just as RAGE is a multiligand receptor, its ligands are also likely to recognize several receptors in mediating their biologic effects.
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Sivenius K, Niskanen L, Voutilainen-Kaunisto R, Laakso M, Uusitupa M. Aldose reductase gene polymorphisms and susceptibility to microvascular complications in Type 2 diabetes. Diabet Med 2004; 21:1325-33. [PMID: 15569136 DOI: 10.1111/j.1464-5491.2004.01345.x] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
AIMS The gene encoding the human aldose reductase, the first and rate-limiting enzyme of the polyol pathway of glucose metabolism, is a promising candidate gene which may contribute to diabetic microvascular complications. We investigated the association of two previously reported DNA sequence variants of this gene, the C-106T polymorphism and the (CA)(n) dinucleotide repeat marker, with the risk of albuminuria and retinopathy in Finnish Type 2 diabetic patients and non-diabetic control subjects. METHODS The study population included 85 Finnish, middle-aged, newly diagnosed Type 2 diabetic patients and 126 non-diabetic control subjects. Genetic analyses were performed using the polymerase chain reaction, restriction fragment length polymorphism, and automated laser fluorescence scanning analyses. Microvascular complications were determined using 10-year follow-up data of urinary albumin excretion measurements and ophthalmological examinations. RESULTS The C and Z-2 alleles of the C-106T polymorphism and the (CA)(n) repeat marker, respectively, were found to be more frequent in Type 2 diabetic subjects than in non-diabetic subjects. The C and Z-2 alleles were in 60% linkage disequilibrium in diabetic subjects. At the time of diagnosis, diabetic subjects with the T allele of the C-106T polymorphism had significantly higher urinary albumin excretion rate and prevalence of albuminuria than subjects with the C-106C genotype (prevalence of albuminuria: 33.3 vs. 13.8%, P = 0.036, odds ratio = 3.9, 95% confidence interval 1.1, 14.7). The Z-2 allele of the (CA)(n) repeat marker was not consistently associated with the prevalence of albuminuria. No associations were observed between the polymorphisms examined and the prevalence of retinopathy at any point of the follow-up. CONCLUSIONS The present study suggests that the C-106T polymorphism of the aldose reductase gene could be involved in the early development of microalbuminuria in Finnish Type 2 diabetic patients.
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Affiliation(s)
- K Sivenius
- Department of Clinical Nutrition, University of Kuopio and Kuopio University Hospital, Kuopio, Finland.
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24
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Abstract
Multiple clinical and physiopathological studies as well as genetic analysis, suggest that diabetic retinopathy (DR) is a consequent of interactions between environmental factors, especially hyperglycaemia, and several genetic factors. The genes of aldose reductase (AR), inducible nitric oxide synthase (NOS2A), endothelial nitric oxide synthase (NOS3), vascular endothelial growth factor (VEGF), pigmented epithelium-derived factor (PEDF), protein kinase C-beta (PKC-beta) and receptor for advanced glycation end products (RAGE) implicated in the pathogenesis of DR. The only genetic marker associated with risk of DR in several studies is a microsatellite (A-C)n at 5'end of AR. The synergistic combination of conventional approaches (e.g. candidate gene association studies) with new emerging technologies (e.g. biochips) will be a key factor in the elucidation of the genetic aspects of DR.
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Affiliation(s)
- M J Taverna
- Laboratoire de Diabétologie, INSERM U.341, Hôpital Hôtel-Dieu, 75004 Paris.
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