Targeting hepatic mitochondrial function in humans with NAFLD using insulin sensitizers

使用胰岛素增敏剂靶向 NAFLD 患者的肝线粒体功能

• 批准号: 10601098
• 负责人: RALPH A DEFRONZO
• 金额: $ 68.22万
• 依托单位: UNIVERSITY OF TEXAS HLTH SCIENCE CENTER
• 依托单位国家: 美国
• 财政年份: 2022
• 资助国家: 美国
• 起止时间: 2022-04-15 至 2027-03-31
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10601098
• 关键词: Acute; Address; Adipose tissue; Agonist; Antioxidants; Benign; Cardiolipins; Cell Nucleus; Cells; Chronic; Cirrhosis; Citric Acid Cycle; Clinical Trials; Coupled; Defense Mechanisms; Development; Disease; Disease Progression; Enzymes; Epidemic; Fatty Acids; Fatty acid glycerol esters; Fibrosis; Fostering; Future; Genomics; Glucose; Goals; Hepatic; High Fat Diet; Human; Inflammatory; Insulin; Insulin Resistance; Knowledge; Life; Lipids; Liver; Liver Mitochondria; Liver diseases; Mediating; Metabolic; Metabolic Diseases; Methodology; Mitochondria; Molecular; Multiple Abnormalities; Mus; Non-Insulin-Dependent Diabetes Mellitus; Obesity; Outcome; Oxidative Stress; PPAR gamma; Pathogenesis; Pathologic; Pathologic Processes; Pathway interactions; Patients; Peripheral; Phospholipids; Physiological; Pioglitazone; Play; Prevalence; Primary carcinoma of the liver cells; Propionates; Public Health; Publishing; Risk; Rodent; Role; Shotguns; Techniques; Testing; Therapeutic; Tracer; Woman; comorbidity; density; design; fatty acid oxidation; glucose metabolism; hepatocellular injury; human subject; in vivo; innovation; insight; insulin sensitizing drugs; lipidomics; liver biopsy; liver injury; liver transplantation; mitochondrial metabolism; new epidemic; non-alcoholic fatty liver; non-alcoholic fatty liver disease; nonalcoholic steatohepatitis; novel; novel strategies; novel therapeutics; oxidation; placebo controlled trial; pleiotropism; preclinical study; pyruvate dehydrogenase kinase 4; response; single nucleus RNA-sequencing; stable isotope; therapeutic target; transcriptomics; treatment strategy; uptake

PROJECT SUMMARY/ABSTRACT Nonalcoholic fatty liver disease (NAFLD) describes a spectrum of liver abnormalities from the relatively benign storage of excess fat in nonalcoholic fatty liver (NAFL) to the more ominous nonalcoholic steatohepatitis (NASH), characterized by hepatocellular injury, necroinflammation, and fibrosis. Liver damage in NASH is the fastest growing cause of hepatocellular carcinoma and is now the most common reason for liver transplantation in women. The prevalence of NAFLD parallels that of obesity, insulin resistance and type 2 diabetes (T2D), and patients with these comorbidities are at greater risk of life-threatening liver outcomes. However, there are no approved treatments for NAFLD and there is an urgent need for new strategies to suppress this emerging epi- demic. Our goal is to employ innovative and highly integrative approaches in human subjects to gain mechanistic insight into the pathogenesis of NAFLD that will foster the development of new therapeutics that address the underlying pathological processes. Early in the course of NAFL, hepatic lipid delivery is increased as a conse- quence of high fat diets, adipose tissue insulin resistance and increased uptake and de novo synthesis of lipids. This metabolic milieu increases mitochondrial density, oxidative capacity and TCA cycle flux in NAFL livers, which eventually may overwhelm antioxidant defense mechanisms to promote the development of NASH. In preclinical studies we observed that the insulin sensitizer and PPARγ agonist pioglitazone directly suppressed elevated hepatic mitochondrial oxidative capacity and TCA cycle activity in these NAFL livers. Therefore, in the following three specific aims we will utilize stable isotope tracer methodology to test the central hypothesis that hepatic mitochondrial function is a targetable feature of NAFLD in humans. In Specific Aim 1 we will first quanti- tate hepatic mitochondrial fluxes across the NAFLD spectrum using a triple stable isotope tracer approach ([U- 13C]propionate, [3,4-13C2]glucose and 2H2O) coupled to 2H and 13C NMR analysis to simultaneously interrogate hepatic glucose metabolism and mitochondrial fluxes in well characterized patients with NAFL and NASH. Next, in Specific Aim 2 we will evaluate hepatic mitochondrial function as a target of insulin sensitizers in humans and will interrogate the contribution of peripheral PPARy agonism on hepatic mitochondrial fluxes and glucose me- tabolism in NAFLD. Finally, in Specific Aim 3 we will determine the mitochondrial mechanisms governing the effect of pioglitazone on NAFLD: In mice with NAFLD using a combination of single-nuclei genomics and shotgun lipidomics approaches to examine parenchymal and non-parenchymal cell transcriptomics and to quantitate mi- tochondrial lipid remodeling, respectively, in liver biopsies obtained following chronic pioglitazone treatment. Collectively, these studies will identify mechanisms that can be exploited in the future to foster the design of novel therapies that safely target T2D and NAFLD.

项目摘要/摘要 非酒精性脂肪肝病（NAFLD）描述了相对良性的肝脏异常 将多余脂肪储存在非酒精脂肪肝（NAFL）中 以肝细胞损伤，坏死症和纤维化为特征。纳什的肝损害是最快的 肝细胞癌的日益增长，现在是肝移植的最常见原因 女性。 NAFLD的患病率与肥胖，胰岛素抵抗和2型糖尿病（T2D）的患病率相似，并且 具有这些合并症的患者面临威胁生命的肝脏结局的更大风险。但是，没有 批准的NAFLD治疗方法，迫切需要采取新的策略来抑制这一新兴的表演 DEMIC。我们的目标是在人类受试者中采用创新且高度综合的方法来获得机理 深入了解NAFLD的发病机理，该发病机理将促进针对新疗法的发展 基础病理过程。在NAFL过程的早期，肝脂质的递送增加了，因为 对高脂饮食，脂肪组织胰岛素抵抗以及脂质的摄取和从头合成的增加。 这种代谢环境增加了Nafl肝脏中的线粒体密度，氧化能力和TCA循环通量， 有时可能会淹没抗氧化剂防御机制，以促进纳什的发展。在 临床前研究我们观察到胰岛素传感器和PPARγ激动剂吡曲霉直接抑制 这些NAFL寿命中的肝脏线粒体氧化能力和TCA循环活性升高。因此，在 遵循三个具体目标，我们将利用稳定的同位素示踪方法来检验中心假设，即 肝线粒体功能是NAFLD在人类中的目标特征。在特定的目标1中，我们将首先进行量化 使用三重稳定的同位素示踪剂方法（[U-） 13c]丙酸，[3,4-13C2]葡萄糖和2H2O）耦合到2H和13C NMR分析，以同时询问 肝葡萄糖代谢和线粒体通量良好的NAFL和NASH患者的线粒体通量。下一个， 在特定目的2中，我们将评估肝脏线粒体功能，作为人类胰岛素传感器的靶标 将询问外周par激动剂对肝线粒体通量和葡萄糖me的贡献 Nafld中的Tabolism。最后，在特定的目标3中，我们将确定控制的线粒体机制 Pioglitazone对NAFLD的影响：使用单核基因组和shot弹枪的NAFLD小鼠在NAFLD中的影响 脂肪组学的方法是检查实质和非辅助细胞转录组学的方法，并定量MI- 在慢性吡格列酮治疗后获得的肝活检中，tooncondrial脂质重塑分别。 总的来说，这些研究将确定将来可以探索的机制，以促进设计 安全针对T2D和NAFLD的新型疗法。