Controlling sphingosine 1-phosphate synthesis and trafficking

控制 1-磷酸鞘氨醇的合成和运输

基本信息

批准号：
9330886
负责人：
KEVIN R. LYNCH
金额：
$ 52.77万
依托单位：
UNIVERSITY OF VIRGINIA
依托单位国家：
美国
项目类别：
财政年份：
2016
资助国家：
美国
起止时间：
2016-09-01 至 2020-08-31
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/9330886
关键词：
Acute Renal Failure with Renal Papillary Necrosis Adrenergic alpha-Antagonists Agonist Animal Model Autoimmune Diseases Bioavailable Biological Assay Biological Availability Biology Blood Blood Vessels Bradycardia Cells Chemicals Chemistry Clinic Clinical Trials Computer Simulation Crystallization Data Development Disease Disease Progression Disease model Docking Dose Drug Kinetics Drug Targeting Endothelial Cells Erythrocytes G-Protein-Coupled Receptors Goals Hematopoietic Stem Cell Mobilization Homology Modeling Human Immune Immune response Immunosuppressive Agents Injury Isoenzymes Kidney Kidney Diseases Lead Leukocytes Libraries Ligands Liquid substance Lymph Lymphocyte Lymphoid Lymphoid Tissue Malignant Neoplasms Mediating Mediator of activation protein Medicine Methanol Methods Molecular Multiple Sclerosis Mus Oral Organ Pathway interactions Pharmaceutical Chemistry Pharmaceutical Preparations Pharmacology Physiological Plasma Prodrugs Productivity Property Pyrrolidines Resolution Rodent Route Sepsis Sickle Cell Sickle Cell Anemia Signal Transduction Signaling Molecule Structure Structure-Activity Relationship Synthesis Chemistry Testing Therapeutic Therapeutic Agents Tissues Validation Virus Diseases Work X-Ray Crystallography base design edg-1 Protein efficacy testing extracellular human disease immune function immunoregulation improved in vivo inhibitor/antagonist insight macular edema mouse model multiple sclerosis patient nanomolar novel novel therapeutic intervention prevent programs scaffold sphingosine 1-phosphate sphingosine kinase structural biology synergism targeted agent tool trafficking

项目摘要

Sphingosine kinases (SphK1, SphK2) catalyze the formation of an important extracellular mediator, sphingosine 1-phosphate (S1P). A fundamental aspect of S1P biology is the large difference in S1P abundance between blood or lymph (high) and tissue (low), which is termed the S1P vascular gradient. This gradient maintains vascular endothelial barrier function and facilitates lymphocyte mobilization from lymphoid tissues. Indeed, S1P1 receptor agonist drugs (e.g. fingolimod) are therapeutically beneficial because S1P signaling is highly sensitive to changes in S1P gradient. We used our SphK2 inhibitors to demonstrate that interdicting S1P signaling at the level of synthesis steepens the S1P vascular gradient by slowing S1P clearance from the blood. This result suggests that SphK2 inhibitors will be extremely useful in treating conditions where the endothelial barrier is compromised, e.g. acute kidney injury and sepsis. Although our recently discovered SphK2 inhibitors are active in vivo, improvements in potency, oral availability and chemical diversity are needed to advance them to the clinic. We will accomplish these goals by generating additional inhibitors on our current chemical scaffold and by developing a novel second scaffold. The current scaffold has also yielded a few SphK1 inhibitors but these lack potency at mouse SphK1, which precludes their testing for efficacy in some key disease models. In contrast to SphK2, inhibition of Sphk1 decreases the S1P vascular gradient and to probe the resulting physiological consequences, multiple inhibitors are needed. We will use iterative rounds of synthesis and testing to generate a library of SphK1 inhibitors with emphases on increasing their potency at mouse SphK1 and discovering inhibitors that have suitable pharmacokinetic properties in rodents. To understand the molecular mechanism of SphK inhibition as well as to inform the synthetic chemistry strategies, we will solve the structures of both isozymes with bound inhibitors using X-ray crystallography. Finally, we will discover a blocker of the S1P exporter, SPNS2, which provides the S1P to lymph and thereby maintains the S1P vascular gradient that is required for lymphocyte egress from lymphoid organs to lymph. Currently, due to the unavailability of SPNS2 inhibitors, this particular approach to the manipulation of S1P gradient and subsequent immunomodulation remains completely unexplored. The strength of our program is the synergism in the combination of chemistry (Santos) and pharmacology (Lynch) to which we now add structural biology (Faham). Our central theme of is to understand the therapeutic potential of manipulating the S1P gradients either at the level of synthesis (SphK inhibition) or transport (SPNS2 blockade). We have a track record of productivity that enabled a fundamental insight into S1P biology, e.g. our discovery that SphK2 inhibition modulates S1P signaling to protect endothelial function, a new therapeutic strategy. Now, we propose the development and detailed characterization of greatly improved SphK inhibitors and to make the chemical tools necessary to interrogate SPNS2 as a potential drug target.

鞘氨醇激酶（SPHK1，SPHK2）催化重要的细胞外介体的形成， 1-磷酸盐（S1P）。 S1P生物学的一个基本方面是S1P的巨大差异血液或淋巴（高）和组织（低）之间的丰度，称为S1P血管梯度。这梯度维持血管内皮屏障功能，并促进淋巴管的淋巴细胞动员组织。实际上，S1P1受体激动剂药物（例如芬洛莫德）在治疗上是有益的，因为S1P 信号对S1P梯度的变化高度敏感。我们使用SPHK2抑制剂证明在合成水平上固定S1P信号传导通过减慢S1P来降低S1P血管梯度从血液中清除。该结果表明SPHK2抑制剂将在治疗中非常有用内皮屏障被损害的条件，例如急性肾脏损伤和败血症。虽然我们的最近发现的SPHK2抑制剂在体内活跃，效力，口服可用性和化学需要多样性才能将它们推向诊所。我们将通过产生更多的目标来实现这些目标对我们当前的化学支架的抑制剂，并通过开发新的第二支架。当前的脚手架还产生了一些SPHK1抑制剂，但是在鼠标SPHK1上缺乏效力，这排除了他们的测试在某些关键疾病模型中的功效。与SPHK2相反，SPHK1的抑制降低了S1P血管为了探测所得的生理后果，需要多种抑制剂。我们将使用迭代的合成和测试回合，以生成SPHK1抑制剂库，重点是增加它们在小鼠SPHK1的效力并发现具有合适药代动力学特性的抑制剂啮齿动物。了解SPHK抑制的分子机制，并告知合成化学策略，我们将使用X射线解决两种同工酶的结构晶体学。最后，我们将发现S1P出口商SPNS2的一个阻滞剂，该扩展器将S1P提供给淋巴，从而维持S1P血管梯度，这是从淋巴样中出口所需的S1P血管梯度器官到淋巴。目前，由于SPNS2抑制剂无法获得，这种特殊的方法 S1P梯度的操纵和随后的免疫调节仍未完全探索。这我们计划的优势是化学（Santos）和药理学（Lynch）组合的协同作用我们现在添加结构生物学（Faham）。我们的中心主题是了解治疗性在合成水平（SPHK抑制）或运输水平下操纵S1P梯度的潜力（SPNS2封锁）。我们有生产力的记录，使S1P具有基本见解生物学，例如我们发现SPHK2抑制作用调节S1P信号传导以保护内皮功能，这是一个新的治疗策略。现在，我们提出了大大改进的发展和详细表征 SPHK抑制剂并制造将SPNS2作为潜在药物靶靶的必要化学工具。