Role of Aldose Reductase in Diabetic Complications

醛糖还原酶在糖尿病并发症中的作用

基本信息

批准号：
8007485
负责人：
SATISH K SRIVASTAVA
金额：
$ 8.5万
依托单位：
UNIVERSITY OF TEXAS MED BR GALVESTON
依托单位国家：
美国
项目类别：
财政年份：
2009
资助国家：
美国
起止时间：
2009-12-31 至 2010-09-30
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/8007485
关键词：
Ablation Affect Alcohols Aldehyde Reductase Aldehydes Animal Model Antibodies Aorta Apoptosis Arts Attenuated Binding Binding Sites Biochemical Blood Vessels Budgets Complex Complications of Diabetes Mellitus Core Facility Cytokine Signaling Development Diabetes Mellitus Electrospray Ionization Functional disorder Funding Gel Generations Genomics Glucose Glutathione Glutathione S-Transferase Goals Grant Hyperglycemia Hyperplasia Inflammation Inflammatory Insulin Resistance Investigation Isoenzymes Knockout Mice Lead Lipids MAP Kinase Gene MAPK8 gene Mediating Molecular Molecular Models Monitor Mus Mutation Nature Nitrosation Oxidases Oxidation-Reduction Oxidative Stress PRKCB1 gene Pathway interactions Phosphorylation Phosphotransferases Physiological Post-Translational Protein Processing Process Production Protein Kinase Proteins Proteomics Reactive Oxygen Species Research Personnel Role Serine Signal Transduction Site Smooth Muscle Myocytes Spectrometry Stress Structure TANK-binding kinase 1 TNF-alpha converting enzyme Techniques Testing Therapeutic Tissue Inhibitor of Metalloproteinases Toxic effect Transcription Factor AP-1 Vascular Endothelial Cell autocrine base clinical efficacy cytokine cytotoxic cytotoxicity diabetic diabetic rat enzyme pathway glutathione analog improved in vivo inflammatory marker inhibitor/antagonist microbial alkaline proteinase inhibitor molecular modeling mutant novel therapeutic intervention paracrine payment polyol prevent protein kinase C beta receptor transcription factor

项目摘要

The polyol pathway enzyme aldose reductase (AR) has been implicated in several pleiotrophic complicationsof diabetes. In animal models, AR inhibitors (ARI) prevent or delay multiple diabetic complications. However, the clinical efficacy of ARI remains uncertain, and the physiological role of AR is unclear. Our results during the current funding period show that AR-catalyzed reduced products of lipid aldehydes-glutathione conjugates (such as GS-DHN, glutathione dihydroxynonane), formed under hyperglycemia-induced oxidative stress, mediate NF-KB and API activation that increases inflammatory markers. We have shown that nitrosation activates and glutathiolation inactivates AR. Our central hypothesis is that by altering the cellular redox state, and inducing post-translational modifications, prolonged diabetes perturbs the redox poise and stress signaling leading to an increase in cytokine production and inflammation which in turn induces or exacerbates secondary diabetic complications. To test this hypothesis, we will extend the studies to understand the mechanistic relationship between hyperglycemia and inflammation and identify the role of AR in cytokine production and inflammation. Specifically our aim is to continue our investigations to further understand the mechanisms by which AR mediates hyperglycemia-induced activation of PKC and TACE that cause TNF-a secretion leading to smooth muscle cell hyperplasia, vascular endothelial cell apoptosis, inflammation, and insulin resistance. Accordingly,the aims are extension of the current grant. Completion of our aims will verify our hypothesis and identify the mechanisms through which AR could mediate hyperglycemia- induced inflammatory signals that cause secondary diabetic complicationsincluding insulin resistance. Also the results of additional structural studies on AR would help us in developing more specific and targeted inhibitor(s) of AR. Thus the aims of the next five years are to: (1) investigate the mechanisms by which reduced lipid aldehydes-glutathione conjugates (such as GS-DHN) in hyperglycemia activate PKC and NF-KB and trigger inflammation; (2) delineate the role of AR in regulating TNF-a production during hyperglycemia; (3) identify protein kinase(s) activated by AR- catalyzed reduced lipid aldehydes-glutathione conjugates (GS-DHN) that phosphorylate PKC; and (4) develop specific and targeted aldose reductase inhibitors. Based on our recent crystal structure of the AR-NADPH-glutathione analogue ternary complex and biochemical analysis of the glutathione binding site of AR, molecular modeling, site-directed mutations will be performed to further probe glutathione binding site and the nature of the interaction between AR and glutathione conjugates. This will help in developing structure-based AR inhibitors which will prevent the binding of GS-HNE without affecting the binding and reduction of toxic lipid aldehydes such as HNE. This approach is potentially important in minimizing the toxicity of AR inhibitors thereby greatly improvingthe therapeutic application of AR inhibitors.

多元型途径酶还原酶（AR）已与几种多otiotiotolophic并发症有关糖尿病。在动物模型中，AR抑制剂（ARI）预防或延迟多种糖尿病并发症。但是， ARI的临床功效仍然不确定，AR的生理作用尚不清楚。我们在当前的结果资金期表明，AR催化的脂质醛醛含量减少了，例如GS-DHN，例如GS-DHN，谷胱甘肽二羟基苯烷），在高血糖诱导的氧化应激下形成，介导NF-KB和API 激活会增加炎症标记。我们已经表明硝化化激活和谷氨酸化灭活AR。我们的中心假设是通过改变细胞氧化还原状态并诱导翻译后修饰，长时间的糖尿病会使氧化还原固定和应力信号传递导致细胞因子的增加产生和炎症又会引起或加剧继发性糖尿病并发症。测试这个假设，我们将扩展研究以了解高血糖和炎症并确定AR在细胞因子产生和炎症中的作用。特别是我们的目标是继续我们的研究以进一步了解AR介导高血糖诱导的激活的机制引起TNF-A分泌的PKC和TACE导致平滑肌细胞增生，血管内皮细胞凋亡，炎症和胰岛素抵抗。因此，目的是延长当前赠款。完成我们的目标将验证我们的假设，并确定AR可以介导高血糖的机制引起炎症信号，引起继发性糖尿病并发症，包括胰岛素抵抗。还有结果关于AR的其他结构研究将有助于我们开发AR的更具体和有针对性的抑制剂。因此接下来的五年的目的是：（1）研究脂质醛减少的机制高血糖中的结合物（例如GS-DHN）激活PKC和NF-KB并触发炎症；（2）描述 AR在高血糖期间调节TNF-A产生中的作用；（3）鉴定由AR-激活的蛋白激酶催化磷酸化pkc的脂质醛降低的脂质醛结合物（GS-DHN）；（4）开发特定和靶向醛糖还原酶抑制剂。基于我们最近的ar-nadph-glutathione类似物的晶体结构 AR的谷胱甘肽结合位点的三元复合物和生化分析，分子建模，位置定向将进行突变以进一步探测谷胱甘肽结合位点以及AR和AR之间相互作用的性质谷胱甘肽结合。这将有助于开发基于结构的AR抑制剂，以防止 GS-HNE不影响有毒脂质醛（例如HNE）的结合和减少。这种方法是在最大程度地限制AR抑制剂的毒性中可能很重要，从而大大改善了治疗应用 AR抑制剂。