Using a Rare Disease Model to Explore the Role of FGF21 in Insulin Resistance

使用罕见疾病模型探索 FGF21 在胰岛素抵抗中的作用

• 批准号: 10538609
• 负责人: Stephen Isaac Stone
• 金额: $ 16.08万
• 依托单位: WASHINGTON UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2021
• 资助国家: 美国
• 起止时间: 2021-04-01 至 2024-12-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/10538609
• 关键词: APOA5 gene; Adipocytes; Adipose tissue; Animals; Area; Biological Assay; Biological Markers; Biological Models; Biology; Biometry; Blood; Body Composition; Body Size; Body Weight decreased; Brown Fat; CRISPR/Cas technology; Case Study; Cell Line; Childhood; Clinical; Communication; Complex; Data; Diabetes Mellitus; Disease; Disease model; Down-Regulation; Endocrinology; Environment; Environmental Risk Factor; Epidemic; Fatty Liver; Fatty acid glycerol esters; Fellowship; Female Adolescents; Fibroblast Growth Factor; Fibroblast Growth Factor Receptor 1; Fibrosis; Foundations; Funding; Future; GLUT 4 protein; Genes; Genetic; Genomic approach; Genomics; Glucose; Goals; Growth; Healthcare; Hepatic; Hormones; Human; Hyperglycemia; Hyperinsulinism; IGF1 gene; Impairment; In Vitro; Individual; Inflammation; Insulin; Insulin Resistance; Investigation; K-Series Research Career Programs; Ketone Bodies; Knock-in Mouse; Knowledge; Lead; Link; Lipodystrophy; Lipolysis; Literature; Liver; Measurement; Measures; Mediating; Mentors; Metabolic; Metabolic syndrome; Molecular; Molecular Biology; Mus; Mutant Strains Mice; Mutation; Non-Insulin-Dependent Diabetes Mellitus; Nonesterified Fatty Acids; Obesity; Parents; Pathogenicity; Patients; Pattern; Pediatric Hospitals; Pediatrics; Phenotype; Physicians; Play; Principal Investigator; Rare Diseases; Recombinant Fibroblast Growth Factor; Research; Research Ethics; Residencies; Resistance; Role; SLC2A1 gene; Scientist; Serum; Siblings; Signal Transduction; Starvation; Syndrome; Testing; Therapeutic Agents; Training; Transgenic Mice; Transgenic Organisms; Triglycerides; United States; Universities; Variant; Washington; Work; adipocyte differentiation; apolipoprotein C-II; autocrine; career development; clinical training; dietary; drug testing; exome sequencing; experience; fatty liver disease; fibroblast growth factor 21; functional genomics; genetic approach; genome editing; glucose uptake; improved; in vivo; induced pluripotent stem cell; insulin sensitivity; laboratory experience; lipid metabolism; mouse model; mutant; non-alcoholic fatty liver disease; novel; pharmacologic; proband; public health relevance; rare condition; receptor; response; skills; transcription factor

Project Summary/Abstract Insulin-mediated pseudoacromegaly (IMPA) is a rare insulin resistance syndrome that is distinct from other insulin resistance syndromes, as it leads to overgrowth and tall stature. Despite the handful of reported cases in the literature, there is no molecular or genetic explanation for this disease. Exome sequencing on an adolescent female with IMPA and her sibling and parents revealed that she carries two rare, potentially deleterious, variants in Fibroblast Growth Factor Receptor 1 (FGFR1) and 𝛽𝛽-Klotho (KLB), which form the receptor complex for Fibroblast Growth Factor 21 (FGF21). We hypothesize that these mutations explain the extreme insulin resistance, tall stature, and lipodystrophy-like phenotype seen in IMPA. To test the function of these FGFR1 and KLB variants in vivo, we used CRISPR/Cas9 genome editing to create a transgenic knock-in mouse line with these variants and corrected the FGFR1 and KLB mutations in an induced pluripotent stem cell (iPSC) line isolated from our proband with IMPA. In this study, we are proposing the following specific aims. In Aim 1, we will determine whether the metabolic and physical phenotype of IMPA mice (with mutations in Fgfr1/Klb) is a consequence of impaired FGF21 signaling. In Aim 2, we will determine if the insulin resistance seen in IMPA is due to impaired adipocyte function. In Aim 3, we will determine the mechanism of fatty liver disease in IMPA mutant mice. In addition to forming a functional genetic approach toward defining a novel insulin resistance syndrome, this four-year proposal outlines a comprehensive strategy for the principal investigator's career development in academic pediatric endocrinology. This strategy logically builds on the principal investigator's previous research experience and clinical training. After obtaining his MD, the principal investigator completed his residency training in general pediatrics, and fellowship in pediatric endocrinology. This proposal now focuses on expanding his scientific skills by attaining additional knowledge and practical research experience in studying a transgenic mouse model of a rare human insulin resistance syndrome. The career development goals will be achieved through a multi-faceted approach involving mentoring by Dr. David Ornitz (fibroblast growth factors and transgenic mouse models) and Dr. Fumihiko Urano (metabolic testing in mice), hands-on laboratory experience, scientific investigation, and training in genetics/genomics, biostatistics, scientific communication, and research ethics. This work will take place in a unique training environment comprised of complementary experiences at Washington University and St. Louis Children's Hospital. Successful completion of this career development award will result in the principal investigator's transition to an independent physician-scientist. Additionally, this work will contribute to a better understanding of the role that FGF21 plays in human insulin resistance, which will provide the foundation for the principal investigator to apply for future R01-level funding.

项目总结/摘要 胰岛素介导的假性肢端肥大症（IMPA）是一种罕见的胰岛素抵抗综合征， 胰岛素抵抗综合征，因为它会导致过度生长和身材高大。尽管报告的案件为数不多， 在文献中，这种疾病没有分子或遗传学解释。青少年的外显子组测序 一名患有IMPA的女性及其兄弟姐妹和父母透露，她携带两种罕见的、潜在有害的变异体 在成纤维细胞生长因子受体1（FGFR 1）和成纤维细胞-Klotho（KLB）中，它们形成受体复合物， 成纤维细胞生长因子21（FGF 21）。我们假设这些突变可以解释 耐药性、高身材和IMPA中观察到的脂肪营养不良样表型。为了测试这些FGFR 1和 在体内KLB变体中，我们使用CRISPR/Cas9基因组编辑来创建转基因敲入小鼠系， 这些变异体并纠正了诱导多能干细胞（iPSC）系中的FGFR 1和KLB突变 从我们的IMPA先证者身上分离出来。在这项研究中，我们提出了以下具体目标。目标1： 将确定IMPA小鼠（具有Fgfr 1/Klb突变）的代谢和物理表型是否是 FGF 21信号传导受损的结果。在目标2中，我们将确定在IMPA中观察到的胰岛素抵抗是否是 因为脂肪细胞功能受损在目标3中，我们将确定IMPA中脂肪肝疾病的机制。 突变小鼠 除了形成一种功能性遗传学方法来定义一种新的胰岛素抵抗综合征外， 一项为期四年的提案概述了首席研究员职业发展的全面战略， 学术儿科内分泌学这一策略逻辑上建立在首席研究员以前的研究基础上 经验和临床培训。获得医学博士学位后，主要研究者完成了住院医师培训 普通儿科学和儿科内分泌学奖学金。这项提案现在的重点是扩大他的 科学技能，获得额外的知识和实际研究经验，在研究转基因 一种罕见的人类胰岛素抵抗综合征的小鼠模型。实现职业发展目标 通过多方面的方法，包括大卫奥尼茨博士（成纤维细胞生长因子和 转基因小鼠模型）和Fumihiko Urano博士（小鼠代谢试验），动手实验室经验， 科学调查，遗传学/基因组学，生物统计学，科学传播和研究方面的培训 伦理这项工作将在一个独特的培训环境中进行， 华盛顿大学和圣路易斯儿童医院。成功完成此职业发展 该奖项将导致主要研究者过渡到一个独立的医生科学家。而且这个 这项工作将有助于更好地理解FGF 21在人类胰岛素抵抗中的作用， 为主要研究者申请未来R 01级资助提供基础。