Mechanism and inhibition of SREBP-dependent cholesterol/lipid metabolism

SREBP依赖性胆固醇/脂质代谢的机制和抑制

• 批准号: 8416797
• 负责人: GERHARD WAGNER
• 金额: $ 58.15万
• 依托单位: HARVARD MEDICAL SCHOOL
• 依托单位国家: 美国
• 财政年份: 2013
• 资助国家: 美国
• 起止时间: 2013-06-03 至 2017-05-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8416797
• 关键词: Affinity; Apolipoprotein E; Atherosclerosis; Binding; Binding Proteins; Binding Sites; Biological Assay; Cardiovascular Diseases; Cardiovascular Pathology; Cardiovascular system; Cell Culture Techniques; Cell Nucleus; Cell Proliferation; Cells; Cellular Assay; Cholesterol; Cholesterol Homeostasis; Complex; Cultured Cells; DNA Microarray Chip; Development; Diabetes Mellitus; Disease; Down-Regulation; EP300 gene; Epitopes; Exhibits; Fatty Acids; Fatty acid glycerol esters; Fatty-acid synthase; Fluorescence Polarization; Gene Activation; Gene Expression; Gene Targeting; Genes; Germ Cells; Goals; Hepatocyte; Hepatotoxicity; Homeostasis; In Vitro; Insulin Resistance; LDL Cholesterol Lipoproteins; Lead; Ligands; Link; Lipids; Liver diseases; Low-Density Lipoproteins; MED15; Measurement; Measures; Mediator of activation protein; Metabolic syndrome; Methods; Microarray Analysis; Molecular; Non-Insulin-Dependent Diabetes Mellitus; Nuclear Translocation; Obesity; Outcome; Pathogenesis; Pharmaceutical Chemistry; Pharmaceutical Preparations; Property; Protein Family; Regulation; Regulatory Element; Research; Resolution; Role; Signal Pathway; Site; Site-Directed Mutagenesis; Specificity; Sterols; Structure; Testing; Therapeutic; Therapeutic Intervention; Transactivation; Transcription Coactivator; Triglycerides; Validation; Virus; Work; base; cancer cell; domain mapping; follow-up; high throughput screening; in vivo; inhibitor/antagonist; insight; lipid metabolism; member; membrane synthesis; metabolomics; mouse model; non-alcoholic fatty liver; novel therapeutics; p300/CBP-Associated Factor; programs; public health relevance; research study; scaffold; screening; small molecule; transcription factor

DESCRIPTION (provided by applicant): Aberrant control of gene expression programs is contributing to the pathogenesis of a number of globally significant diseases, including cardiovascular disease (CVD), obesity, and diabetes. Members of the sterol regulatory element-binding protein (SREBP) family of transcription factors controls genes involved in cholesterol/lipid metabolism, membrane synthesis, and fat storage. Aberrant SREBP activity has been linked to conditions associated with metabolic syndrome, such as insulin resistance, obesity, elevated LDL-C and triglycerides, cardiovascular pathologies, and non-alcoholic fatty liver disease. Furthermore, SREBPs have been implicated in cancer cell proliferation and replication of enveloped viruses through regulation of membrane synthesis. We have previously defined the molecular requirements for gene activation by SREBPs, demonstrating a central role for the MED15 subunit of the Mediator co-activator complex and the CBP/p300 acetyltransferases. While most therapeutic approaches aimed at altering gene expression programs target upstream signaling pathways or nuclear translocation checkpoints, our studies have provided mechanistic insights supporting an alternative approach, which is aimed at directly inhibiting the interaction of the SREBP transactivation domains (TADs) with MED15 and CBP/p300 co-activators in the nucleus. The goal of the proposed research is to elucidate the mechanisms by which the SREBP transcriptional activators interact with co-activators, and to develop specific small-molecule inhibitors of these interactions. Through a combination of structural and biophysical methods in conjunction with high-throughput screening of small molecules, we propose to use structural insights to guide the development of new classes of therapeutics against cardiovascular and other diseases. In preliminary work, we have already been able to identify small-molecule inhibitors capable of disrupting SREBP-TAD binding to MED15, resulting in concomitant down-regulation of its target genes, such as fatty acid synthase (FASN). Inhibitors emerging from these studies will be optimized with medicinal chemistry. We will pursue the following specific aims: Specific Aim 1: Characterize structurally and functionally the SREBP interaction with co-activators MED15 and CBP/p300. Specific Aim 2: Discover and characterize in vitro small-molecule inhibitors of the SREBP-TAD interaction with co-activators to develop therapeutics against aberrant cholesterol/lipid metabolism. Specific Aim 3: Functionally characterize identified SREBP/co-activator inhibitors using both cell culture and mouse models.

描述（由申请人提供）：基因表达程序的异常控制有助于许多全球重大疾病的发病机制，包括心血管疾病（CVD）、肥胖症和糖尿病。固醇调节元件结合蛋白（SREBP）家族转录因子的成员控制参与胆固醇/脂质代谢、膜合成和脂肪储存的基因。异常的SREBP活性与代谢综合征相关的疾病有关，如胰岛素抵抗、肥胖、LDL-C和甘油三酯升高、心血管病理和非酒精性脂肪肝。此外，SREBP通过调节膜合成参与癌细胞增殖和包膜病毒的复制。我们以前已经定义了SREBP基因激活的分子要求，证明了MED 15亚基的介体共激活复合物和CBP/p300乙酰转移酶的核心作用。虽然大多数旨在改变基因表达程序的治疗方法靶向上游信号通路或核易位检查点，但我们的研究提供了支持替代方法的机制见解，该方法旨在直接抑制SREBP反式激活结构域（TADs）与细胞核中MED 15和CBP/p300共激活因子的相互作用。该研究的目的是阐明SREBP转录激活因子与辅激活因子相互作用的机制，并开发这些相互作用的特异性小分子抑制剂。通过结合结构和生物物理方法以及小分子的高通量筛选，我们建议使用结构见解来指导开发针对心血管和其他疾病的新类别疗法。在初步工作中，我们已经能够鉴定出能够破坏SREBP-BMP 3与MED 15结合的小分子抑制剂，从而导致其靶基因（如脂肪酸合成酶（FATCH））的伴随下调。这些研究中出现的抑制剂将通过药物化学进行优化。我们将追求以下具体目标：具体目标1：在结构和功能上表征SREBP与共激活剂MED 15和CBP/p300的相互作用。具体目标二：发现和表征SREBP-ESTs与共激活剂相互作用的体外小分子抑制剂，以开发针对异常胆固醇/脂质代谢的治疗剂。具体目标3：使用细胞培养和小鼠模型对已鉴定的SREBP/共激活因子抑制剂进行功能表征。