Developing helical peptide antagonists of the growth hormone receptor

开发生长激素受体的螺旋肽拮抗剂

• 批准号: 10648820
• 负责人: Justin Matthew Holub
• 金额: $ 41.53万
• 依托单位: OHIO UNIVERSITY ATHENS
• 依托单位国家: 美国
• 财政年份: 2023
• 资助国家: 美国
• 起止时间: 2023-09-30 至 2025-09-29
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10648820
• 关键词: Acromegaly; Affect; Age of Onset; Aging; Amino Acid Sequence; Animal Model; Anterior Pituitary Gland; Binding; Biochemical; Biological; Biological Assay; Body Composition; Cell Line; Cell model; Cells; Childhood; Clinical; Cultured Cells; Data; Derivation procedure; Development; Diabetes Mellitus; Disease; Disulfide Linkage; Electrophoretic Mobility Shift Assay; FDA approved; Fluorescence Polarization; Foundations; Future; Goals; Growth; Growth Hormone Receptor; Heterogeneity; IGFBP3 gene; In Vitro; Injections; Insulin; Insulin-Like Growth Factor I; Laboratories; Laboratory mice; Lead; Life; Liver; Longevity; Malignant Neoplasms; Mammals; Marketing; Mediating; Metabolism; Molecular; Morbidity - disease rate; Mus; Nodular glomerulosclerosis; Organ; Patients; Peptides; Phenotype; Phosphorylation; Production; Proliferating; Proteins; Receptor Gene; Recombinant Growth Hormone; Recombinant Proteins; Research Personnel; Research Project Grants; Resistance; Series; Serum; Side; Signal Transduction; Somatotropin; Stat5 protein; Structure; Structure-Activity Relationship; Testing; Therapeutic; Therapeutic Intervention; Tissues; Variant; Vertebrates; Work; age related; alpha helix; antagonist; cancer type; cell growth; clinical application; cost; design; diabetic; experimental study; gel mobility shift assay; healthy aging; hormonal signals; immunogenicity; improved; in vivo; interest; mimetics; mouse model; novel; novel therapeutics; organ growth; overexpression; pegvisomant; peptide hormone; pleiotropism; polypeptide; postnatal; proliferative diabetic retinopathy; protein aminoacid sequence; protein folding; protein structure; reproductive; therapeutic protein; transcription factor; translational therapeutics

PROJECT SUMMARY Growth hormone (GH) is a single-chain polypeptide that acts as a key stimulator of cell growth, proliferation and metabolism in mammals. GH acts to promote longitudinal growth and proper organ development during child- hood and stimulates production of insulin-like growth factor 1 (IGF-1) in the liver and other tissues throughout life. Numerous studies have indicated that reduced GH activity in vivo results in healthy aging and increased lifespan; in fact, the longest-lived laboratory mouse results from global disruption of the GH receptor (GHR) gene. Notably, such GHR-/- mice have demonstrated enhanced resistance to GH-mediated disorders that contribute to unhealthy aging, including diabetic end organ damage and certain types of cancer. This connection between reduced GH action and extended lifespan has led to the hypothesis that inhibiting GH action may delay the onset of age-related morbidities. Peptides represent an attractive class of molecule to serve as therapeutic leads because they can be designed to mimic the variable structures and sequences of protein interaction domains. Moreover, peptides are sequence specific and synthetically tractable, allowing them to circumvent many of the production problems associated with protein-based drugs. Our group recently identified a novel peptide-based GHR antagonist (termed SH1) that mitigates GH-mediated signaling in cultured cell lines. S1H was designed as a direct sequence mimic of a small helical region (residues 36-51) of GH that interacts with the GHR. Structure activity relationships of S1H showed a strong correlation between peptide helicity and GHR antagonism, leading us to hypothesize that helical propensity is required for biological activity. We now seek to test this hypothesis by developing S1H derivatives that fold into stable helical structures and use them to inhibit GH-mediated signaling in vitro and in vivo. In aim 1 of this proposal, we will synthesize two separate classes of structured S1H derivative. The first class will be generated by installing olefinic side chains into the wild-type S1H sequence so the peptides can be ‘stapled’ into a-helical structures. The second class will be developed by transposing S1H residues onto the a-helix of scyllatoxin, a small protein that folds into a stable a/b motif. The resulting peptides will then be used in a series of direct binding and electrophoretic mobility shift assays against recombinant GHR. In aim 2, we will investigate the ability of our structured S1H derivatives to inhibit GH signaling in cells that overexpress the GHR and in vivo mouse models of aging. First, we will employ a cell-based surrogate assay to determine whether structured S1H derivatives can inhibit GH-mediated phosphorylation of downstream transcription factors, such as STAT5. Next, we will assess how structured S1H derivatives affect the serum levels of IGF-1 and IGF-BP3, and body composition of C57BL6 mice. Data generated from this proposal will serve as a foundation for future studies that explore the molecular mechanisms through which S1H (and its structured derivatives) affects GH-mediated signaling and will identify potential lead compounds to be used as emerging therapeutics designed to mitigate GH-mediated disorders that contribute to unhealthy aging.

项目概要 生长激素 (GH) 是一种单链多肽，是细胞生长、增殖和生长的关键刺激剂。 哺乳动物的新陈代谢。 GH 的作用是促进儿童时期的纵向生长和适当的器官发育。 并刺激肝脏和其他组织中胰岛素样生长因子 1 (IGF-1) 的产生 生活。大量研究表明，体内 GH 活性降低会导致健康衰老并增加 寿命;事实上，最长寿的实验室小鼠是由于 GH 受体 (GHR) 基因的整体破坏造成的。 值得注意的是，此类 GHR-/- 小鼠已表现出对 GH 介导的疾病的抵抗力增强，这些疾病有助于 不健康的衰老，包括糖尿病终末器官损伤和某些类型的癌症。之间的这种联系 GH 作用减少和寿命延长导致了这样的假设：抑制 GH 作用可能会延迟发病 与年龄相关的疾病。肽代表了一类有吸引力的分子，可以作为治疗先导药物 因为它们可以被设计来模拟蛋白质相互作用域的可变结构和序列。 此外，肽具有序列特异性且易于合成，使它们能够规避许多 与蛋白质药物相关的生产问题。我们的团队最近发现了一种新型的基于肽的 GHR 拮抗剂（称为 SH1）可减轻培养细胞系中 GH 介导的信号传导。 S1H被设计为 与 GHR 相互作用的 GH 小螺旋区域（残基 36-51）的直接序列模拟。结构 S1H 的活性关系显示肽螺旋性和 GHR 拮抗作用之间存在很强的相关性， 我们假设螺旋倾向是生物活性所必需的。我们现在试图检验这个假设 通过开发折叠成稳定螺旋结构的 S1H 衍生物并用它们来抑制 GH 介导的 体外和体内信号传导。在本提案的目标 1 中，我们将综合两类不同的结构化 S1H 衍生物。第一类将通过将烯属侧链安装到野生型 S1H 序列中来生成，因此 肽可以被“钉合”成α螺旋结构。第二类将通过转置S1H来开发 青蛤毒素 a 螺旋上的残基，青蛤毒素是一种小蛋白质，可折叠成稳定的 a/b 基序。所得肽 然后将用于一系列针对重组 GHR 的直接结合和电泳迁移率变化测定。 在目标 2 中，我们将研究我们的结构化 S1H 衍生物抑制细胞中 GH 信号传导的能力， 过度表达 GHR 和体内衰老小鼠模型。首先，我们将采用基于细胞的替代分析来 确定结构化 S1H 衍生物是否可以抑制 GH 介导的下游磷酸化 转录因子，例如 STAT5。接下来，我们将评估结构化 S1H 衍生物如何影响血清水平 IGF-1 和 IGF-BP3 以及 C57BL6 小鼠的身体成分。该提案生成的数据将作为 为未来的研究奠定基础，探索 S1H（及其结构）的分子机制 衍生物）影响 GH 介导的信号传导，并将识别潜在的先导化合物，以用作新兴的 旨在减轻 GH 介导的导致不健康衰老的疾病的疗法。