FoxO1 protects the heart against ischemia

FoxO1 保护心脏免受缺血

• 批准号: 10204793
• 负责人: Junichi Sadoshima
• 金额: $ 57.52万
• 依托单位: RBHS-NEW JERSEY MEDICAL SCHOOL
• 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 2023-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/10204793
• 关键词: Adaptor Signaling Protein; Address; Affinity; Apoptosis; Apoptotic; Arrhythmia; Autophagocytosis; Binding; CCAAT-Enhancer-Binding Proteins; Cardiac; Cardiac Myocytes; Cell Death; Cell Maintenance; Cell Nucleus; Cell Survival; Cell physiology; Cells; Cessation of life; Clinical; Complex; Consensus; DNA Binding; DNA Binding Domain; Development; Dissociation; Elements; FOXO1A gene; Family; Feedback; Gene Delivery; Genes; Genetic Transcription; Heart; Heart failure; Homodimerization; Insulin Resistance; Intervention; Investigation; Ischemia; Knock-in Mouse; Knock-out; Knowledge; Lead; Manganese; Mediating; Molecular; Mus; Myocardial; Myocardial Infarction; Myocardial Ischemia; Myocardial Reperfusion; Oxidative Stress; PMAIP1 gene; Pathway interactions; Patients; Phosphorylation; Phosphotransferases; Physiological; Physiology; Play; Proteins; Proteomics; Regulation; Reperfusion Therapy; Role; SIRT1 gene; Serine; Starvation; Sterility; Stimulus; Stress; Superoxide Dismutase; TNFSF10 gene; Testing; Threonine; cardioprotection; catalase; innovation; mouse model; myocardial injury; novel; peroxiredoxin 2; postnatal; promoter; response; transcription factor

Summary Forkhead box protein O (FoxO) family transcription factors are evolutionarily conserved proteins that play essential roles during development and in postnatal physiology in the heart. FoxOs play a dichotomous role in the regulation of cell survival/death in a context-dependent manner: they mediate cardiomyocyte (CM) cell death under some conditions but promote cell survival under other conditions. FoxOs can promote cell death by stimulating transcription of Bim, TRAIL, FasL, Bcl-6 and NOXA or lead to insulin resistance by downregulating IRS. On the other hand, endogenous FoxOs promote CM survival in response to oxidative stress and mediate the pro-survival effects of Sirt1 in CMs during ischemia/reperfusion (I/R). Moreover, FoxO1- dependent transcription of autophagy genes is required for survival of CMs during starvation. At present, however, how FoxOs mediate their dichotomous cellular functions is not well understood. Better understanding of the underlying mechanisms may make it possible to promote only the salutary function of FoxO1 while inhibiting the pro-death function of FoxO1 in the heart in the clinical setting. Our preliminary results suggest that Mst1, a pro-apoptotic kinase, can convert FoxO1 from pro-apoptotic to pro-survival through sequential phosphorylation of FoxO1 and C/EBP- in CMs. Our overall hypothesis is that Mst1 converts the function of the transcription factor FoxO1 from pro-apoptotic to pro-survival through sequential phosphorylation of FoxO1 at the DNA binding domain (DBD) and C/EBP-at Thr250 (mouse). We will: Aim 1 Show that FoxO1 promotes CM survival during myocardial ischemia and I/R through Mst1-induced phosphorylation of at the DBD; Aim 2 Demonstrate that Mst1 induces dissociation of FoxO1 from the promoter of pro- apoptotic FoxO target genes and association with C/EBP- to promote transcription of pro-survival molecules; Aim 3 Demonstrate that Mst1-induced phosphorylation of C/EBP- at Thr250 is FoxO1- dependent, and that Thr250 phosphorylation of C/EBP- promotes transcription of pro-survival factors; Aim 4 Demonstrate that C/EBP- phosphorylation at Thr250 is salutary and plays an essential role in mediating the salutary effect of the Mst1-FoxO1 pathway during ischemia and I/R. We will use cardiac- specific FoxO1 knockout (KO) (FoxO1cKO) and cardiac-specific C/EBP- KO (C/EBP- cKO) mice, as well as newly generated C/EBP- (T250E) knock-in (KI) mice in conjunction with AAV-mediated gene delivery and proteomics. Our study will elucidate the molecular mechanism by which FoxO transcription factors regulate directionally opposite cellular functions, namely survival and death, in a coordinated manner and through interaction with Mst1 and C/EBP-. Knowledge obtained from this study should be useful for the development of molecular interventions to convert the function of FoxO transcription factors from dichotomous to fully cardioprotective and facilitate survival of CMs in the setting of myocardial injury.

概括 叉头盒蛋白 O (FoxO) 家族转录因子是进化上保守的蛋白质，其作用 FoxOs 在心脏发育和出生后生理学中发挥着双重作用。 以上下文相关的方式调节细胞存活/死亡：它们介导心肌细胞 (CM) FoxOs 在某些条件下会导致细胞死亡，但在其他条件下会促进细胞存活。 通过刺激 Bim、TRAIL、FasL、Bcl-6 和 NOXA 的转录或导致胰岛素抵抗 另一方面，内源性 FoxO 会下调 IRS，从而促进 CM 对氧化反应的存活。 在缺血/再灌注 (I/R) 期间，Sirt1 在 CM 中发挥应激作用并介导其促生存作用。 目前，自噬基因的依赖转录是CM在饥饿期间生存所必需的。 然而，FoxOs 如何介导其二分细胞功能尚不清楚。 潜在机制的研究可能使得仅促进 FoxO1 的有益功能成为可能，而 我们的初步结果表明，在临床环境中抑制 FoxO1 在心脏中的促死亡功能。 Mst1是一种促凋亡激酶，可以通过顺序将FoxO1从促凋亡转变为促生存 CM 中 FoxO1 和 C/EBP- 的磷酸化 我们的总体假设是 Mst1 转换了 的功能。 通过 FoxO1 的连续磷酸化，转录因子 FoxO1 从促凋亡变为促存活 DNA 结合域 (DBD) 和 Thr250（小鼠）的 C/EBP- 我们将： 目标 1 显示 FoxO1。 通过 Mst1 诱导的 at 磷酸化促进心肌缺血和 I/R 期间的 CM 存活 DBD；目标 2 证明 Mst1 诱导 FoxO1 从 pro- 启动子解离 凋亡 FoxO 靶基因并与 C/EBP- 关联以促进促生存转录 分子；目标 3 证明 Mst1 诱导的 C/EBP- Thr250 磷酸化为 FoxO1- C/EBP- 的 Thr250 磷酸化可促进促生存因子的转录； 目标 4 证明 Thr250 处的 C/EBP- 磷酸化是有益的，并且在 在缺血和 I/R 期间介导 Mst1-FoxO1 通路的有益作用我们将使用心脏-。 特异性 FoxO1 敲除 (KO) (FoxO1cKO) 和心脏特异性 C/EBP- KO (C/EBP- cKO) 小鼠，以及 新生成的 C/EBP- (T250E) 敲入 (KI) 小鼠与 AAV 介导的基因传递相结合， 我们的研究将阐明 FoxO 转录因子调节的分子机制。 方向相反的细胞功能，即生存和死亡，以协调的方式并通过 与 Mst1 和 C/EBP- 的相互作用 从本研究中获得的知识应该对开发有用。 分子干预将 FoxO 转录因子的功能从二分法转变为完全分法 在心肌损伤的情况下具有心脏保护作用并促进 CM 的存活。