Targeted Delivery of S100B Inhibitory Peptide to SCA1 Mouse Cerebellum

S100B 抑制肽靶向递送至 SCA1 小鼠小脑

• 批准号: 7990138
• 负责人: DRAZEN RAUCHER
• 金额: $ 7.45万
• 依托单位: UNIVERSITY OF MISSISSIPPI MED CTR
• 依托单位国家: 美国
• 财政年份: 2010
• 资助国家: 美国
• 起止时间: 2010-05-01 至 2012-04-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7990138
• 关键词: Address; Amino Acid Sequence; Ataxia; Binding; Biopolymers; Blood - brain barrier anatomy; Brain Stem; Brain region; CAG repeat; Cell Nucleus; Cells; Cellular Morphology; Central Nervous System Diseases; Cerebellar Ataxia; Cerebellum; Cessation of life; Clinical Trials; Dendritic Spines; Development; Drug Kinetics; Elastin; Engineering; Fever; Figs - dietary; Genes; Goals; Heating; Impairment; Intravenous; Kinetics; Label; Local Hyperthermia; Measures; Mediating; Modeling; Motor; Mus; Neurodegenerative Disorders; Neurophysiology - biologic function; Neuroprotective Agents; Pathology; Peptides; Phosphorylation; Physiological; Plasma; Proteins; Purkinje Cells; Radio; Research; Route; Signal Transduction; Site; Solutions; Stress; TRTK-12 peptide; Technology; Temperature; Therapeutic; Tissues; Toxic effect; Treatment Efficacy; Type 1 Spinocerebellar Ataxia; Vacuole; Work; aqueous; ataxin-1; bactenecin; base; cell type; design; effective therapy; improved; in vivo; interest; mouse model; mutant; nervous system disorder; new technology; novel; polyglutamine; polypeptide; pre-clinical; prevent; public health relevance; response; targeted delivery; tool

DESCRIPTION (provided by applicant): Spinocerebellar ataxia-1 (SCA1) is a devastating neurological disorder, resulting from CAG repeat expansion in the ataxin-1 gene. The polyglutamine expanded mutant ataxin-1 primarily targets Purkinje cells (PCs) of the cerebellum. The exact mechanism of PC degeneration in SCA1 is poorly understood, but it is known that the earliest morphologic change seen in SCA1 PCs is the development of cytoplasmic vacuoles that contain Bergmann glial (BG) proteins, especially S100B. These vacuoles are toxic and alter PC morphology, and may be forming in response to a stress signal of PCs. Furthermore, S100B released by BG or from the vacuoles may modulate Akt phosphorylation of mutant ataxin-1. Akt is known to stabilize mutant ataxin-1 to aggregate in the nucleus of PCs. The objective of the proposed study is to target SCA1 PCs with therapeutic peptide (TP) that will influence ataxin-1 aggregation and toxicity. Though TPs are designed to inhibit specific molecular interactions, their efficacy in vivo is limited by poor pharmacokinetic parameters. To improve their pharmacokinetics and bio-distribution, TP will be fused to a thermally responsive polypeptide-based carrier. This polypeptide can be targeted to the cerebellum of Tg mice by applying local hyperthermia. The amino acid sequence of the thermally responsive polypeptide is based on elastin-like polypeptide (ELP) biopolymers, which are soluble in aqueous solution below physiological temperature, but aggregate when the temperature is raised above 39oC. A cell-penetrating peptide (CPP) is conjugated to the ELP to enhance delivery of the polypeptide across the blood brain barrier (BBB) and to facilitate cell entry. To the CPP-ELP, therapeutic peptide TRTK-12, which interacts with S100B will be conjugated. This TP will be administered intranasally (IN) or intraperitoneally (IP) and, by applying local hyperthermia, it will be demonstrated that these genetically engineered polypeptides can be targeted to a diseased site and improve motor coordination and cerebellar pathology in a SCA1 mouse model. This project will address the following specific aims: Specific Aim 1: Determine feasibility of delivering Bac-ELP or SynB1-ELP IN or IP to the cerebellum. The plasma kinetics and the in vivo distribution of radio-labeled Bac/SynB1-ELP will be measured in the cerebellum, other brain regions and tissues in a SCA1 mouse with and without hyperthermia. Specific Aim 2: Evaluate the therapeutic efficacy TRTK-12 attached to the optimal CPP-ELP as determined in Specific Aim 1. It is anticipated that TP treatment will result in improved motor coordination and PC pathology and will provide preclinical support for the therapeutic potential of this novel technology. Though the SCA1 mouse will be used as a model in the proposed work, this approach could also be applied to thermal targeting of ELP-fused TPs to many other CNS disorders. Therefore, successful completion of the proposed research may have a significant impact, by not only propelling this technology into clinical trials, but also providing a powerful tool to treat and manage other CNS diseases. PUBLIC HEALTH RELEVANCE: Spinocerebellar ataxia-1 (SCA1) is a devastating neurological disease resulting from CAG repeat expansion in the ataxin-1 gene, leading to polyglutamine expansion at the protein level, and degeneration of Purkinje cells as well as some other cell types in the brainstem. Currently, there is no specific treatment to delay or halt the progression of SCA1. We plan to use a very unique strategy of thermally targeted delivery of candidate therapeutic peptides to the cerebellum via intranasal or intravenous routes with the goal of developing useful new strategies for treating SCA1 and other ataxias.

描述（由申请人提供）：脊髓小脑性共济失调-1 (SCA1) 是一种毁灭性的神经系统疾病，由 ataxin-1 基因中的 CAG 重复扩增引起。聚谷氨酰胺扩增的突变体 ataxin-1 主要靶向小脑的浦肯野细胞 (PC)。 SCA1 PC 变性的确切机制尚不清楚，但已知 SCA1 PC 中最早的形态变化是含有伯格曼胶质 (BG) 蛋白（尤其是 S100B）的细胞质液泡的发育。这些液泡是有毒的，会改变 PC 的形态，并且可能是响应 PC 的应激信号而形成的。此外，BG 或液泡释放的 S100B 可能调节突变 ataxin-1 的 Akt 磷酸化。已知 Akt 可以稳定突变的 ataxin-1，使其在 PC 细胞核中聚集。本研究的目的是用治疗肽 (TP) 靶向 SCA1 PC，从而影响 ataxin-1 聚集和毒性。尽管 TP 旨在抑制特定的分子相互作用，但其体内功效受到较差的药代动力学参数的限制。为了改善其药代动力学和生物分布，TP 将与热响应多肽载体融合。通过局部热疗，这种多肽可以靶向Tg小鼠的小脑。热响应多肽的氨基酸序列基于弹性蛋白样多肽（ELP）生物聚合物，其在低于生理温度的水溶液中可溶，但当温度升高到39℃以上时会聚集。细胞穿透肽 (CPP) 与 ELP 缀合，以增强多肽穿过血脑屏障 (BBB) 的递送并促进细胞进入。与 S100B 相互作用的治疗肽 TRTK-12 将缀合至 CPP-ELP。该TP将通过鼻内（IN）或腹膜内（IP）给药，通过局部热疗，将证明这些基因工程多肽可以靶向患病部位，并改善SCA1小鼠模型的运动协调性和小脑病理学。该项目将实现以下具体目标： 具体目标 1：确定将 Bac-ELP 或 SynB1-ELP IN 或 IP 输送到小脑的可行性。将在有或没有高温的 SCA1 小鼠的小脑、其他大脑区域和组织中测量放射性标记的 Bac/SynB1-ELP 的血浆动力学和体内分布。具体目标 2：评估 TRTK-12 附加到具体目标 1 中确定的最佳 CPP-ELP 的治疗效果。预计 TP 治疗将改善运动协调性和 PC 病理学，并将为这项新技术的治疗潜力提供临床前支持。尽管 SCA1 小鼠将在拟议的工作中用作模型，但这种方法也可以应用于将 ELP 融合的 TP 热靶向许多其他 CNS 疾病。因此，成功完成拟议的研究可能会产生重大影响，不仅推动这项技术进入临床试验，而且还为治疗和管理其他中枢神经系统疾病提供强大的工具。 公共卫生相关性：脊髓小脑性共济失调 1 (SCA1) 是一种毁灭性的神经系统疾病，由 ataxin-1 基因中的 CAG 重复扩增引起，导致蛋白质水平上的聚谷氨酰胺扩增，以及浦肯野细胞以及脑干中一些其他细胞类型的变性。目前，没有特定的治疗方法可以延缓或阻止 SCA1 的进展。我们计划使用一种非常独特的策略，通过鼻内或静脉内途径将候选治疗肽热靶向递送至小脑，目标是开发治疗 SCA1 和其他共济失调的有用新策略。