Hyperpolarized 13C probes for the one carbon metabolism

用于一碳代谢的超极化 13C 探针

• 批准号: 10647293
• 负责人: Zoltan Kovacs
• 金额: $ 45.1万
• 依托单位: UT SOUTHWESTERN MEDICAL CENTER
• 依托单位国家: 美国
• 财政年份: 2023
• 资助国家: 美国
• 起止时间: 2023-08-01 至 2025-07-31
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10647293
• 关键词: Adult; Anabolism; Attention; Back; Biochemical Pathway; Biological; Cancer Patient; Carbon; Cell Culture Techniques; Cell Proliferation; Cell physiology; Cells; Chemicals; Citric Acid Cycle; Communities; Cytoplasm; Cytosol; Development; Enzymes; Excretory function; Folic Acid; Formates; Funding; Generations; Glycine; Glycine Hydroxymethyltransferase; Glycolysis; Hematoma; Human; Image; In Vitro; Label; Magnetic Resonance Imaging; Malignant Neoplasms; Metabolic; Metabolism; Mitochondria; Monitor; Neoplasm Metastasis; Nuclear; Nucleotide Biosynthesis; Nucleotides; Organ; Oxidoreductase; Pathway interactions; Pattern; Phospholipids; Polyamines; Primary carcinoma of the liver cells; Process; Production; Prognosis; Proliferating; Rattus; Reaction; Relaxation; Role; Running; S-Adenosylhomocysteine; S-Adenosylmethionine; Serine; Signal Transduction; Source; Testing; Tetrahydrofolates; Time; Tissues; Tracer; Visualization; Warburg Effect; Xenograft procedure; cancer cell; cancer type; clinical translation; experience; hepatoma cell; imaging modality; in vivo; liver cancer model; magnetic resonance spectroscopic imaging; non-invasive imaging; nucleotide metabolism; overexpression; preservation; real time monitoring; tumor

Abstract One-carbon metabolism is a network of fundamental metabolic and biosynthetic pathways that occur in the cytoplasm and the mitochondria. Central to one-carbon metabolism is the folate cycle. This involves the activation and transfer of serine hydroxymethyl group to tetrahydrofolate intermediates and eventually formate, which is then converted back into serine to via the same intermediates. The folate cycle provides activated one carbon units for the biosynthesis of a variety of biomolecules necessary for normal cellular function and proliferation, most importantly, nucleotides. The activity of one-carbon metabolism is upregulated in cancer cells to support high rates of proliferation. The folate cycle is highly compartmentalized with separate sets of enzymes in the cytosol and in the mitochondria. When there is an increased need for one-carbon units for nucleotide biosynthesis, the cytosolic and mitochondrial folate cycles run in the opposite direction. The mitochondrial folate pathway produces formate, which is transported into the cytosol where it enters the folate cycle to produce activated one-carbon units for biosynthesis. In many types of cancer cells, the mitochondrial formate production exceeds the biosynthetic demand. Excess formate is excreted from these cells in a process known as formate overflow. Despite its great biological importance and central role in cancer, currently there is no clinically translatable, non–invasive imaging method for the real time monitoring of one carbon metabolism and formate overflow in vivo. In this R21 application we propose to use deuterated, 13C-labeled serines as hyperpolarized 13C-tracers to monitor one carbon metabolic activity and formate overflow in vivo by 13C magnetic resonance spectroscopic imaging. As serine is the main source of one carbon units, 13C-labeled serines are ideal probes for the mitochondrial folate cycle. Aim 1 will focus on the synthesis and in vitro characterization of deuterated, 13C-labeled serines as hyperpolarized 13C probes for the one carbon metabolism. In Aim 2, we will test the hyperpolarized probes in hepatoma cell cultures and in vivo in normal and orthotopic xenograft rat model for hepatocellular carcinoma. By the end of the two year funding period we expect to have demonstrated that upregulated mitochondrial folate pathway can be visualized in hepatoma bearing rats by 13C magnetic resonance spectroscopic imaging.

抽象的 单碳代谢是一个基本的代谢和生物合成途径的网络 细胞质和线粒体。一碳代谢的中心是叶酸周期。这涉及 丝氨酸羟基激活和转移至四氢叶酸中间体，并最终形成 然后通过相同的中间体将其转换回序列。叶酸周期提供了激活的一个 用于正常细胞功能和 增殖，最重要的是核动肽。一碳代谢的活性在癌症中更新 细胞支持高增殖速率。叶酸周期被高度分室，单独的一组 细胞质和线粒体中的酶。当对单碳单元的需求增加时 核苷酸生物合成，胞质和线粒体叶酸循环沿相反方向延伸。这 线粒体叶酸途径产生形式，该途径被转运到叶酸的细胞质中 循环产生活化的一碳单元进行生物合成。在许多类型的癌细胞中，线粒体 形式产量超过了生物合成需求。在一个过程中，这些单元超过了过量形式 称为形式溢出。尽管具有生物学重要性和在癌症中的核心作用，但目前有 没有用于实时监测一种碳代谢的临床翻译，非侵入性成像方法 并在体内形成溢出。在此R21应用程序中，我们建议将13c标记的丝氨酸用作 超极化13C追踪器监测一种碳代谢活性，并在体内形成溢出13C 磁共振光谱成像。由于丝氨酸是一个碳单元的主要来源，因此标记为13C 丝氨酸是线粒体叶酸周期的理想问题。 AIM 1将集中于合成和体外 将氘代，13C标记的丝氨酸作为一个碳的超极化13C问题的表征 代谢。在AIM 2中，我们将测试肝瘤细胞培养物中的超极化探针和正常的体内 用于肝细胞癌的原位异种移植大鼠模型。到两年资金期结束时，我们 期望证明可以在肝瘤中可视化更新的线粒体叶酸途径 通过13C磁共振光谱成像轴承大鼠。