Role of TBK1/IKK epsilon inhibition in pancreatic beta cell regeneration

TBK1/IKK epsilon 抑制在胰腺 β 细胞再生中的作用

• 批准号: 9539010
• 负责人: CHONG H SHIN
• 金额: --
• 依托单位: GEORGIA INSTITUTE OF TECHNOLOGY
• 依托单位国家: 美国
• 财政年份: 2017
• 资助国家: 美国
• 起止时间: 2017-09-01 至 2017-09-02
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/9539010
• 关键词: Address; Adult; Architecture; B Cell Proliferation; Beta Cell; Biochemical; Biological Availability; Cell Count; Cell physiology; Cyclic AMP; Data; Development; Diabetes Mellitus; Enhancers; Exhibits; FRAP1 gene; Failure; Functional disorder; Genetic; Genetic Screening; Goals; Human; IKKepsilon; Immune; Immune response; Impairment; In Vitro; Infection; Inflammatory Response; Insulin; Insulin Resistance; Insulin-Dependent Diabetes Mellitus; Interferons; Islets of Langerhans; Lead; Mediating; Metabolic; Mitogens; Modeling; Molecular; Mus; Natural regeneration; Obese Mice; Oral; Outcome; Pathway interactions; Peptides; Phosphotransferases; Play; Residual state; Role; Signal Transduction; Sirolimus; Specificity; Streptozocin; Structure of beta Cell of islet; Structure-Activity Relationship; System; TANK-binding kinase 1; Testing; Therapeutic; Toxic effect; Transgenic Organisms; Validation; Zebrafish; acrylic acid; amlexanox; analog; azastene; blood glucose regulation; chemical genetics; design; drug candidate; glucose metabolism; glycemic control; improved; in vivo; inhibitor/antagonist; insulin sensitivity; islet; kinase inhibitor; mouse model; novel; overexpression; scaffold; screening; small molecule; small molecule inhibitor

Diabetes mellitus is characterized by impaired glucose homeostasis resulting from insufficiency or functional failure of insulin-producing β−cells, alone or in association with insulin resistance. Therefore, restoring β-cell mass and function is essential to reverse the development of diabetes. Utilizing small molecule inducers of β-cell proliferation is a particularly promising strategy with numerous valuable features such as their oral bioavailability and target specificity. However, the slow rate of β-cell proliferation in adult humans is a major hurdle to overcome to use this approach. Through a chemical genetic screen for small molecule enhancers of β-cell regeneration in zebrafish, we identified several TBK1/IKKε inhibitors (TBK1/IKKε-Is). TBK1/IKKε-Is promoted β-cell regeneration by markedly increasing proliferation of β-cells. Mammalian target of rapamycin (mTOR) inhibitor rapamycin eliminated the effect of TBK1/IKKε-Is on regenerating β-cells, whereas TBK1/IKKε-Is augmented mTOR activity. Interestingly, treatment with TBK1/IKKε-Is led to pronounced increase in cAMP levels. The proliferation effect of TBK1/IKKε-Is was verified in primary mammalian islets including human islets. The goal of this application is to delineate the mechanisms and the strategies of how to increase functional β-cell mass with suppression of TBK1/IKKε. First, we will design and investigate the potency of novel TBK1/IKKε-Is on β-cell regeneration. Using (E)-3-(3-phenylbenzo[c]isoxazol-5-yl)acrylic acid (abbreviated as PIAA), which markedly increases β-cell regeneration, as a lead compound, we will perform structure-activity relationship (SAR) analyses of TBK1/IKKε-PIAA interaction. Furthermore, we will use the PIAA as a scaffold to design new molecular architectures that exhibit potent and selective TBK1/IKKε inhibition activities with minimum toxicity on β-cell regeneration. Second, we will elucidate underlying mechanisms of TBK1/IKKε-mediated β-cell regeneration. Given that rapamycin treatment abolished the effect of TBK1/IKKε suppression on β-cell regeneration and TBK1/IKKε-Is enhanced mTOR activity and cAMP levels, we will test whether TBK1/IKKε suppression promotes β-cell regeneration via modulating the cAMP-mTOR signaling cascade. We will perform biochemical and functional analyses to characterize the TBK1/IKKε-cAMP-mTOR interplay on β-cell regeneration in vitro and in vivo. Third, we will investigate the efficacy of TBK1/IKKε-Is on expanding functional β-cell mass in mammalian systems. We will use primary pancreatic islets to examine the potency of PIAA and its newly synthesized analogs on β-cell replication. Furthermore, we will evaluate the ability of PIAA and its analogs to promote β-cell expansion and enhance glycemic control in mice including a mouse model of streptozotocin (STZ)-induced diabetes.

糖尿病的特征是由于产生胰岛素的 β 细胞不足或功能衰竭而导致葡萄糖稳态受损，无论是单独的还是与胰岛素抵抗相关的，因此，恢复 β 细胞的质量和功能对于逆转糖尿病的发展至关重要。 β细胞增殖的分子诱导剂是一种特别有前途的策略，具有许多有价值的特征，例如口服生物利用度和靶点特异性，然而，成年人体内β细胞增殖速度缓慢是一个需要克服的主要障碍。通过对斑马鱼 β 细胞再生的小分子增强剂进行化学遗传筛选，我们发现了几种 TBK1/IKKε 抑制剂 (TBK1/IKKε-Is) 通过显着增加 β 细胞再生。哺乳动物雷帕霉素靶点 (mTOR) 抑制剂雷帕霉素消除了 TBK1/IKKε-Is 对β细胞增殖的影响。 TBK1/IKKε-Is 可以促进 β 细胞的再生，而 TBK1/IKKε-Is 则隐含地增强了 mTOR 活性，而 TBK1/IKKε-Is 的治疗则导致 cAMP 水平显着增加。本申请的目的是阐明如何通过抑制 TBK1/IKKε 来增加功能性 β 细胞质量的机制和策略。使用 (E)-3-(3-苯基苯并[c]异恶唑-5-基)丙烯酸（缩写为 PIAA）设计并研究新型 TBK1/IKKε-Is 对 β 细胞再生的功效，可显着增加 β 细胞。 -细胞再生，作为先导化合物，我们将对 TBK1/IKKε-PIAA 相互作用进行结构活性关系 (SAR) 分析 此外，我们将使用 PIAA。作为设计新分子结构的支架，该结构表现出有效和选择性的 TBK1/IKKε 抑制活性，并且对 β 细胞再生的毒性最小。 其次，我们将阐明 TBK1/IKKε 介导的 β 细胞再生的潜在机制。 TBK1/IKKε 抑制对 β 细胞再生的影响以及 TBK1/IKKε-Is 增强 mTOR 活性和 cAMP 水平的影响，我们将测试是否TBK1/IKKε 抑制通过调节 cAMP-mTOR 信号级联促进 β 细胞再生。我们将进行生化和功能分析，以表征 TBK1/IKKε-cAMP-mTOR 在体外和体内对 β 细胞再生的相互作用。我们将研究 TBK1/IKKε-Is 在哺乳动物系统中扩大功能性 β 细胞量的功效。我们将使用原代胰岛来检查 PIAA 的效力。此外，我们将评估 PIAA 及其类似物促进 β 细胞扩增和增强小鼠血糖控制的能力，包括链脲佐菌素 (STZ) 诱导的糖尿病小鼠模型。