Structure-based optimization of a novel pharmacological chaperone therapy for MPSIIIC

基于结构的 MPSIIIC 新型药理学伴侣疗法的优化

基本信息

批准号：
9343249
负责人：
GEOFFREY A CHANG
金额：
$ 22.49万
依托单位：
PHOENIX NEST, INC.
依托单位国家：
美国
项目类别：
财政年份：
2017
资助国家：
美国
起止时间：
2017-09-15 至 2020-08-31
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/9343249
关键词：
Acetyl Coenzyme A Acetyltransferase Active Sites Address Adolescent Adult Affect Affinity Area Behavioral Biological Assay Biology Blood - brain barrier anatomy CRISPR/Cas technology California Carbohydrates Cells Child Childhood Cognitive Common Core Crystallization Cultured Cells DNA Sequence Alteration Data Defect Dementia Deterioration Disease Dose Drug Kinetics Economics Ensure Enzymes Family Funding Future Glucosamine Glycosaminoglycans Glycosphingolipids Goals Grant Health Healthcare Systems Heparitin Sulfate Hepatomegaly High Pressure Liquid Chromatography Hyperactive behavior Hypertrichosis In Vitro Inherited Institutes Knock-in Knock-in Mouse Knowledge Discovery Life Lysosomal Storage Diseases Lysosomes MDCK cell Measures Medical Membrane Proteins Mental Retardation Metabolic Diseases Minor Missense Mutation Modeling Modification Molecular Chaperones Molecular Conformation Mucopolysaccharidoses Mucopolysaccharidosis III Mutate Nerve Degeneration Neurodegenerative Disorders Neurologic Pathology Patients Penetration Permeability Pharmaceutical Chemistry Pharmaceutical Preparations Pharmacologic Substance Pharmacology Phase Primates Probability Property Proteins Proteoglycan Rare Diseases Recombinants Research Residual state Resolution Roentgen Rays Route Scientist Sleep Disorders Small Business Technology Transfer Research Speech Stretching Structure Surface System Techniques Technology Testing Therapeutic Tissues Toxic effect Universities Visceral Work X-Ray Crystallography analog base biophysical properties clinical candidate clinical phenotype cytotoxicity demented design drug discovery early childhood effective therapy enzyme activity enzyme deficiency enzyme replacement therapy enzyme structure experience hearing impairment improved in vitro testing in vivo infancy inhibitor/antagonist insight joint stiffness mouse model mutant neurobehavioral neuropsychiatry novel pre-clinical preclinical study prevent professor response small molecule social vertebra body

项目摘要

PROJECT SUMMARY Lysosomal storage diseases (LSD) are rare inherited metabolic disorders caused by defects in the cellular catabolic system. Mucopolysaccharidosis Type IIIC (MPS IIIC or Sanfilippo disease type C) is one such LSD that is caused by deficiency of the enzyme heparan sulfate acetyl CoA: α-glucosaminide N-acetyltransferase, (HGSNAT) essential for degradation of heparan sulfate, a repeating carbohydrate generally found attached to proteoglycans. This disease causes accumulation of heparan sulfate and results in progressive and severe neurological deterioration early in life. Most patients become demented and die before adulthood but some survive to the fourth decade with progressive dementia. Currently there is no specific treatment for MPS III and enzyme replacement therapy may not be viable as the recombinant enzyme may have difficulty crossing the blood brain barrier. The disease can however be considered as an excellent candidate for so-called chaperone therapy (where active site specific inhibitors or other small molecules restore some activity of a mutant enzyme) because a threshold activity of approximately 10% of the normal level should be sufficient to prevent storage based on in vitro data. Thus, even such a minor increase in residual enzyme activity as the result of chaperone therapy is likely to have an impact on disease pathology and be beneficial for patients. Recently our collaborator Dr. Pshezhetsky has identified an inhibitor and a chaperone for HGSNAT (AT3784) and demonstrated that it could partially restore the deficient enzyme activity in the cells from MPS IIIC patients, however more potent chaperones need to be identified for a therapy for MPS IIIC. The goal of this STTR is to resolve the tertiary structure of HGSNAT and use this information to direct the synthesis of potent inhibitors/chaperones of HGSNAT. Synthesized compounds will be tested in vitro for their ability to increase the residual HGSNAT activity in cultured cells from MPS IIIC patients. Active compounds that increase enzyme activity by > 10% will be further tested for their ability to reduce storage of heparan sulfate and to stabilize the proper conformation and targeting of the mutant enzyme in cultured patient cells. As a stretch goal we will investigate the ability of the best compound to cross the blood brain barrier. Compounds identified in this preclinical study will provide leads for future phase II in vivo testing and optimization that will be performed in the extension of this project (Phase II) using knock-in mouse models of MPS IIIC generated using the CRISPR Cas9 technology. This proposal leverages the vast X-ray crystallography experience of Professor Geoffrey Chang (University of California San Diego), extensive pharmaceutical medicinal chemistry experience of Dr. Joel Freundlich (Rutgers University), MPSIIIC biology expertise of Dr. Alexey Pshezhetsky (CHU Ste-Justine) and drug discovery knowledge of Sean Ekins (Phoenix Nest, Inc.). Dr. Pshezhetsky’s work on this project will be entirely funded by funds outside this grant including Jonah’s Just Begun or the Canadian Institutes of Health Research. If successful, Phase II will lead to a clinical candidate for studies which will leverage our large global network of clinicians and other scientists as needed.

项目概要溶酶体贮积病（LSD）是一种罕见的遗传性代谢性疾病，由细胞缺陷引起 IIIC 型粘多糖贮积症（MPS IIIC 或 C 型 Sanfilippo 病）就是这样一种 LSD。这是由于硫酸乙酰肝素乙酰辅酶A缺乏引起的：α-氨基葡萄糖N-乙酰转移酶， (HGSNAT) 对于硫酸乙酰肝素的降解至关重要，硫酸乙酰肝素是一种通常附着在这种疾病会导致硫酸乙酰肝素的积累，并导致进行性和严重的症状。大多数患者在生命早期就会出现痴呆并在成年前死亡，但也有一些患者。患有进行性痴呆，可存活到四十岁。目前尚无针对 MPS III 和 MPS III 的具体治疗方法。酶替代疗法可能不可行，因为重组酶可能难以穿过然而，这种疾病可以被认为是所谓的伴侣的绝佳候选者。疗法（其中活性位点特异性抑制剂或其他小分子恢复突变体的某些活性酶），因为阈值活性约为正常水平的 10% 应足以防止基于体外数据的储存因此，即使是残留酶活性的微小增加。最近我们的伴侣疗法可能会对疾病病理学产生影响并对患者有益。合作者 Pshezhetsky 博士发现了 HGSNAT (AT3784) 的抑制剂和伴侣它可以部分恢复 MPS IIIC 患者细胞中表现出的酶活性缺陷，然而，需要确定更有效的伴侣来治疗 MPS IIIC。该 STTR 的目标是解析 HGSNAT 的三级结构并使用此信息指导有效的合成 HGSNAT 的抑制剂/伴侣将在体外测试其增加的能力。 MPS IIIC 患者培养细胞中残留的 HGSNAT 活性增加酶的活性化合物。活性> 10% 将进一步测试其减少硫酸乙酰肝素储存和稳定作为一个延伸目标，我们将在培养的患者细胞中确定突变酶的正确构象和靶向。研究本文中确定的最佳化合物穿过血脑屏障的能力。临床前研究将为未来的 II 期体内测试和优化提供线索，这些测试和优化将在使用 CRISPR 生成的 MPS IIIC 敲入小鼠模型来扩展该项目（第二阶段） Cas9技术。该提案利用了 Geoffrey Chang 教授（University of University）丰富的 X 射线晶体学经验。（加州圣地亚哥）Joel Freundlich 博士拥有丰富的药物化学经验（罗格斯大学），Alexey Pshezhetsky 博士（CHU Ste-Justine）的 MPSIIIC 生物学专业知识和药物 Sean Ekins（Phoenix Nest, Inc.）的发现知识将完全由 Pshezhetsky 博士在该项目上的工作完成。由本次赠款之外的基金资助，包括乔纳刚刚开始或加拿大健康研究所。如果成功，第二阶段将产生临床候选研究，该研究将利用我们庞大的全球网络战士和其他需要的科学家。