Hypoxia, HIF-1, and the progression of nonalcoholic fatty liver disease in obstructive sleep apnea

阻塞性睡眠呼吸暂停中的缺氧、HIF-1 和非酒精性脂肪肝的进展

• 批准号: 10436877
• 负责人: Omar Mesarwi
• 金额: $ 17.76万
• 依托单位: UNIVERSITY OF CALIFORNIA, SAN DIEGO
• 依托单位国家: 美国
• 财政年份: 2019
• 资助国家: 美国
• 起止时间: 2019-07-01 至 2024-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/10436877
• 关键词: Animals; Antisense Oligonucleotides; Cessation of life; Chronic; Cirrhosis; Communication; Data; Data Analyses; Development; Disease; Disease Progression; Disease model; Enzymes; Event; Experimental Designs; Family; Fatty Liver; Fibrosis; Fostering; Genetic Transcription; Glucose; Goals; Hepatic; Hepatic Stellate Cell; Hepatocyte; Histologic; Hypoxia; Hypoxia Inducible Factor; Impairment; In Vitro; Inflammation; Insulin Resistance; Knock-out; Knowledge; Kupffer Cells; Laboratories; Laboratory Procedures; Lead; Link; Liver; Liver Failure; Liver Fibrosis; Liver diseases; Malignant neoplasm of liver; Mediating; Mediator of activation protein; Mentors; Metabolic; Metabolic dysfunction; Metabolic syndrome; Methods; Modeling; Mus; Obesity; Obstructive Sleep Apnea; Oxygen; Pathogenicity; Pathway interactions; Patients; Pharmacology; Phenotype; Physicians; Play; Proteins; RNA Interference; Recurrence; Research; Rodent; Role; Scientist; Severities; Sleep; Techniques; Testing; Therapeutic; Training; Training Programs; Transplantation; Whole-Genome Shotgun Sequencing; Work; adverse outcome; career; cell type; design; diet-induced obesity; disease phenotype; fatty acid metabolism; glucose metabolism; glucose output; human subject; hypoxia inducible factor 1; in vivo; in vivo Model; insight; knock-down; laboratory experience; lipid metabolism; liver hypoxia; liver injury; liver metabolism; mouse model; non-alcoholic fatty liver disease; nonalcoholic steatohepatitis; prevent; response; sensor; skills; therapeutic target; tool; transcriptome sequencing

PROJECT SUMMARY/ABSTRACT The objectives of this K08 proposal are: a) To foster the development of critical scientific and professional skills which will allow the candidate, Dr. Omar Mesarwi, to progress toward his goal of becoming an independent physician-scientist, examining the metabolic consequences of obstructive sleep apnea (OSA); and b) To determine how intermittent hypoxia (IH) in OSA may impact the development and progression of nonalcoholic fatty liver disease (NAFLD). Dr. Mesarwi and his mentors at UC San Diego have designed a comprehensive training plan that will afford Dr. Mesarwi new knowledge and research skills in the pathobiology of metabolic dysfunction in OSA. This will be accomplished through extensive laboratory experience and coursework at UC San Diego, which will provide Dr. Mesarwi additional expertise in experimental design, laboratory procedures, data analysis, and scientific communication. OSA is a common condition which is characterized by recurrent upper airway narrowing during sleep, leading to chronic IH. OSA is associated with a more severe NAFLD phenotype, driven by IH. NAFLD is an extremely prevalent condition in which hepatic steatosis and dysregulated glucose metabolism may ultimately lead to cirrhosis, need for transplant, and liver-related death. The mechanisms which link OSA and NAFLD are relatively unknown. Previous animal work has demonstrated that IH exacerbates hepatic steatosis and fibrosis in mice with diet-induced obesity, mirroring findings in human subjects. Hepatic steatosis in experimental NAFLD reduces liver oxygen tension; it is further reduced with superimposed IH. Hepatic steatosis also increases hypoxia inducible factor-1 (HIF-1), a regulator of the cellular response to hypoxia. We have shown that hepatocyte HIF-1 mediates the expression of several key enzymes of fatty acid metabolism in the liver, and the progression of liver fibrosis in experimental NAFLD. Therefore, we hypothesize that IH in OSA may worsen the NAFLD phenotype through HIF-1 activation and its downstream effects. We will test this hypothesis in three Specific Aims: 1) Determine the role of HIF-1 as a mediator of IH- induced hepatic steatosis and dysregulated hepatic glucose metabolism; 2) Determine the role of HIF-1 on IH- induced hepatic fibrosis in mice with experimental NAFLD, and the effect of antisense oligonucleotides targeting HIF-1α in reversing liver fibrosis; and 3) Determine the role of HIF-1 and IH in mediating liver fibrosis in other hepatic cell types. Tools available to us include cell type-specific HIF-1α knockout, which will help localize HIF-1 effects. Major methods for this proposal include co-modeling OSA and NAFLD in rodents, antisense knockdown of hepatic HIF-1α, RNA interference, and whole genome shotgun sequencing (RNA- Seq). Successful implementation of these Specific Aims will provide a rigorous training program for Dr. Mesarwi, laying the groundwork for R01 submission, and will allow us to answer a fundamentally important question about the role of hypoxia and HIF-1 in patients with OSA and NAFLD, and possibly to credential HIF-1 and/or its downstream mediators as therapeutic targets in preventing metabolic derangement in OSA.

项目总结/文摘