Novel Medicinal Chemicals: Cardiomyogenesis from Human Stem Cells

描述(申请人提供)：超过1-2%的65岁以上的美国人患有心脏病。根据美国心脏协会的数据，心力衰竭是西方世界65岁以上患者住院的最常见原因之一，随着人口老龄化，这种情况只会变得更糟。目前，有500多万美国人患有心力衰竭。2009年，美国社会每年因心脏病造成的经济损失(直接和间接)超过370亿美元。某些与心脏肌肉衰竭或心肌衰弱相关的疾病可以通过药物或设备治疗，如除颤器、起搏器或植入式泵。然而，在心脏病发作时，当心肌细胞死亡时，移植成为唯一的选择，因为人类心脏中的心肌细胞再生通常非常有限。不幸的是，今天可用的心脏移植组织比目前的移植需求要少得多。每年可以使用数万颗心脏进行移植，但可用的心脏只有大约2000颗。胚胎干细胞(ESC)研究的化学生物学方法为纠正这一问题提供了相当大的希望。然而，尽管取得了进展，但提高干细胞或祖细胞成为人类心肌细胞的效率一直是非常具有挑战性的。提高心肌细胞产量的主要问题是缺乏有效的方法来诱导ESCs提供参与心脏发生的心肌细胞。一个关键的问题是体外分化过程中心肌细胞的产量很低。需要一种经济上可行的生物技术过程，使用容易获得和廉价的分化试剂。在这里，我们建议使用高含量和高通量细胞分析和动态药物化学的强大组合来开发纯的、易于制作的小分子“工具箱”化合物来促进hESCs的诱导分化为心肌细胞。一种有希望的新的心肌细胞分化药物(即化合物1)已经被确定，该药物的改进和开发是本提案的重点。具体目标包括：1)在经过验证的小鼠ESC试验中测试结构上与1相关的化合物作为心肌细胞的诱导剂；2)在经过验证的人类ESC试验中测试Aim 1中确定的有效化合物用于心肌细胞分化。基于我们令人鼓舞的初步结果，拟议工作的成功完成将提供一个廉价的试剂工具箱，用于从生物技术意义上从有用的人胚胎干细胞诱导心肌细胞。以这种方式制备人类心肌细胞将提供大量的心肌细胞，并将广泛用于CRO、生物技术或大型制药行业，以帮助包括心肌梗死在内的心力衰竭患者，并对人类心肌细胞进行药物安全性测试，以减少药物-药物的不良相互作用，开发更安全的药物。 公共卫生意义：对于心脏病患者，干细胞疗法可能提供一种再生受损心肌细胞的方法。目前的治疗方法只能改善心脏功能。我们的工作目标是利用化学生物学来开发小分子“工具箱”化合物，这种化合物将刺激干细胞分化并产生心肌细胞。最终，这项工作的结果将提供用于培养心肌细胞的试剂，用于治疗心脏病的生物技术过程。

DESCRIPTION (provided by applicant): Over 1-2% of Americans greater than 65 years of age have heart disease. According to the American Heart Association, heart failure is one of the most common causes of hospitalization for patients over 65 years of age in the Western world and as the population ages, this situation will only get worse. Currently, more than 5 million Americans suffer from heart failure. In 2009, the economic cost (direct and indirect) to US society for heart disease was in excess of $37 billion per year. Certain diseases related to heart muscle failure or heart muscle weakening are treatable with drugs or devices such as defibrillators, pacemakers or implanted pumps. However, in heart attacks, when heart muscle cells die, transplantation becomes the only option because cardiomyocyte regeneration in the human heart is generally very limited. Today, unfortunately, there is considerably less heart transplantation tissue available than the current need for transplants. Tens of thousands of hearts could be used each year for transplants but only about 2,000 hearts are available. Chemical biology approaches to embryonic stem cell (ESC) research offers considerable promise for rectifying this problem. However, despite progress, increasing the efficiency of stem or progenitor cells to become human cardiomyocytes has been very challenging. The main problem with increasing the yield of cardiomyocytes is the lack of effective ways to induce ESCs to afford cardiomyocytes involved in cardiogenesis. A critical issue is the low yields of cardiomyocytes from in vitro differentiation processes. An economically viable biotechnological process using readily available and inexpensive differentiation agents is needed. Herein, we propose to use a powerful combination of high content and high throughput cellular assays and dynamic medicinal chemistry to develop pure, easy to make, small molecule "toolbox" compounds to promote the induction of hESCs that will differentiate into cardiomyocytes. A promising new cardiomyocyte differentiation agent (i.e., compound 1) has been identified and refinement and development of this agent is the focus of this proposal. The Specific Aims include: 1) Test compounds structurally related to 1 as inducers of cardiomyocytes in a validated mouse ESC assay and 2) Test potent compounds identified in Aim 1 in a validated human ESC assay for cardiomyocyte differentiation. Based on our encouraging Preliminary Results successful completion of the proposed work will provide an inexpensive toolbox of reagents useful for the induction of cardiomyocytes from human ESCs of utility in a biotechnological sense. Preparation of human cardiomyocytes in this manner will provide large numbers of cardiomyocytes and will be of widespread use to the CRO, biotechnology or Big Pharma industry to help individuals that suffer from heart failure including myocardial infarct as well as to do drug safety tests with human cardiomyocytes to decrease adverse drug-drug interactions and develop safer drugs. PUBLIC HEALTH RELEVANCE: For heart attack victims, stem cell therapy may provide a way to regenerate damaged heart muscle cells. Current therapies are only able to improve heart function. The goal of our work is to use chemical biology to develop small molecule "toolbox" compounds that will stimulate stem cell differentiation and produce cardiomyocytes. Ultimately, the results from this work will provide reagents for use to grow cardiomyocytes for use in a biotechnology process to treat heart disease.