High-Throughput Screen For FDA Approved Drugs That Amplify Beta-Cell Mass In Vivo

描述(由申请人提供)：FDA批准的在体内放大β细胞团的药物的高通量筛选这里提出的项目的目的是确定将在治疗糖尿病方面具有治疗作用的药物。I型(或青少年)糖尿病是由胰腺中产生胰岛素的细胞慢性丧失引起的。如果没有胰岛素，身体就无法调节血糖水平，从而导致不利的病理。控制脊椎动物胰腺发育的分子机制高度保守；因此，我们转向斑马鱼作为研究细胞生物学的替代模型系统。由于斑马鱼幼体较小，适合于多孔板的单孔内，它们是唯一适合进行高通量化学筛选的脊椎动物模型系统。寻找新的治疗药物的最大问题之一是从发现到药物进入临床之间的巨大滞后。为了加快这一过程，我们使用了两种方法：1)直接在动物模型中测试药物；2)我们正在筛选的化合物库-约翰·霍普金斯药物库(JHDL)-是一个独特的资源，主要是FDA批准的药物。因此，无论目前使用何种药物，在我们的研究中发现的任何FDA治疗药物都将有一个更快的进入临床和人体试验的途径。我们发表的工作表明，鱼类胰腺次级胰岛中的细胞形成在功能上等同于哺乳动物的细胞新生。因此，导致鱼类幼体早期细胞分化的药物被假设也可以诱导哺乳动物的细胞新生。使用转基因斑马鱼，我们进行了药物筛选，寻找早熟细胞形成的诱导剂。从3347种接受评估的药物中，我们确定了5种“成功”。作为这项提议的一部分，我们计划在I型糖尿病小鼠模型中验证这些“Hit”化合物。此外，我们打算重新研究JHDL，以寻找在我们最初筛选中没有测试的浓度下发挥作用的化合物，并在协同组合中测试有希望的线索。最后，我们将为第二个屏幕开发工具。这项后续筛查将再次使用转基因斑马鱼，但目的将是识别诱导内源性细胞增殖的化合物。在我们的两个屏幕之间，我们的目标是找到能够诱导细胞形成并增加其持续生产的化合物。通过这种方式，我们希望找到FDA批准的药物，这些药物将增加人类的细胞量，并将在治疗糖尿病方面具有治疗作用。我们还打算利用我们的细胞生物学知识来阐明我们识别的药物的作用模式。这将进一步加深我们对细胞新生的理解，并揭示可以用来开发更好治疗方法的分子途径。我们为筛选而开发的方法和技术本质上是通用的，基于报告蛋白的相对表达水平。因此，这些技术将对研究广泛的人类疾病的研究人员产生相当大的兴趣。 与公共健康相关：FDA批准的在体内放大Beta细胞团的药物的高通量筛选为了努力寻找糖尿病的治疗方法，我们刚刚完成了对斑马鱼幼体的创新高通量筛选。我们筛选了FDA批准的药物库中可导致细胞分化的化合物。通过在我们最初的筛查中验证最有效的诱导细胞形成的药物，以及在我们提议的第二次筛查中验证诱导增殖的药物，最终我们的目标是找到能够增加人类细胞质量的药物。

DESCRIPTION (provided by applicant): High-throughput screen for FDA approved drugs that amplify Beta-cell mass in vivo The aim of the project proposed here is to identify drugs that will be therapeutic in the treatment of Diabetes. Type I (or Juvenile) Diabetes is caused by a chronic loss of the insulin-producing ¿-cells of the pancreas. Without insulin the body fails to regulate blood glucose levels leading to adverse pathology. There is a high degree of conservation in the molecular mechanisms that control vertebrate pancreas development; therefore, we have turned to the zebrafish as an alternative model system to study ¿-cell biology. As zebrafish larvae are small, and fit inside single wells of multiwell plates, they are the only vertebrate model system suited for carrying out high-throughput chemical screens. One of the largest problems in finding new therapeutic drugs is the huge lag between discovery and getting the drug into the clinic. To expedite this process, we use two approaches: 1) drugs are tested directly in animal models, and 2) the compound library we are screening - the Johns Hopkins Drug Library (JHDL) - is a unique resource of mainly FDA approved drugs. Thus, regardless of current use, any FDA drug found to be therapeutic in our research will have a significantly faster route into the clinic, and human trials. Our published work has shown that ¿-cell formation in the secondary islets of fish pancreata is functionally equivalent to ¿-cell neogenesis in mammals. Hence, drugs that cause early differentiation of ¿-cells in fish larvae are hypothesized to also induce ¿-cell neogenesis in mammals. Using transgenic zebrafish we performed a drug screen for inducers of precocious ¿-cell formation. From 3347 drugs evaluated we identified 5 'Hits'. As part of this proposal, we plan to validate these 'Hit' compounds in murine models of Type I diabetes. Furthermore, we intend to reinvestigate the JHDL to search for compounds that function at concentrations not tested in our initial screen, and to test promising leads in synergistic combinations. Finally, we will develop the tools for a second screen. This follow-up screen will again use transgenic zebrafish but will be aimed at identifying compounds that induce proliferation of endogenous ¿-cells. Between our 2 screens we aim to find compounds that induce ¿-cell formation and increase their continued production. In this way we hope to find FDA approved drugs that will increase ¿-cell mass in humans and that will be therapeutic in the treatment of diabetes. We also intend to use our knowledge of ¿-cell biology to elucidate the mode of action of the drugs we identify. This will further our understanding of ¿-cell neogenesis and reveal molecular pathways that could be exploited to develop better therapies. The methods and technologies we have developed for our screening are universal in nature, being based on relative expression levels of reporter proteins. Thus, these techniques will be of considerable interest to researchers investigating a wide array of human diseases. PUBLIC HEALTH RELEVANCE: High-throughput screen for FDA approved drugs that amplify Beta-cell mass in vivo In an effort to find therapies for diabetes, we have just finished an innovative high-throughput screen on larval zebrafish. We screened a library of FDA approved drugs for compounds that cause differentiation of ¿-cells. By validating the drugs most effective at inducing ¿-cell formation from our initial screen and drugs that induce proliferation in our proposed second screen, ultimately we aim to find drugs that can increase ¿-cell mass in humans.