Circadian Regulation of In Vitro Differentiated Adipocytes

体外分化脂肪细胞的昼夜节律调节

• 批准号: 10534917
• 负责人: Armina-Lyn M Frederick
• 金额: $ 4.68万
• 依托单位: DARTMOUTH COLLEGE
• 依托单位国家: 美国
• 财政年份: 2022
• 资助国家: 美国
• 起止时间: 2022-07-01 至 2025-11-30
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10534917
• 关键词: Address; Adipocytes; Adipose tissue; Adopted; Affect; Binding; Bioenergetics; Biological Clocks; Biology; Bypass; Cell physiology; Cells; Cellular biology; Cessation of life; Chronic; Chronic Disease; Circadian Rhythms; Confocal Microscopy; Coupled; Creatine; Cues; Data; Disease; Elements; Energy Metabolism; Enzymes; Epidemic; Feedback; Fluorescence; Functional disorder; Futile Cycling; Gene Expression Profiling; Genes; Genetic Transcription; Genomics; Goals; Homeostasis; Hour; Human body; Hyperplasia; Hypertrophy; Image; In Vitro; Learning; Light; Link; Lipids; Mediating; Messenger RNA; Metabolic; Metabolic Control; Metabolic syndrome; Metabolism; Mitochondria; Mitotic; Molecular; Monitor; Morphology; Mus; Nutrient; Obesity; Oligomycins; Organelles; Output; Pathway interactions; Pattern; Periodicity; Phase; Phenotype; Physiological; Physiology; Process; Production; Protons; Purine Nucleotides; Research; Resolution; Respiration; Risk; Risk Factors; Role; Sleep Wake Cycle; Stimulus; System; Systems Biology; Temperature; Testing; Thermogenesis; Time; Tissues; Vision; Weight; Western Blotting; Work; adipocyte biology; adipocyte differentiation; bioinformatics tool; cell type; circadian; circadian pacemaker; circadian regulation; glucose metabolism; lipid metabolism; live cell microscopy; luminescence; transcriptome sequencing; uncoupling protein 1

ABSTRACT Metabolic dysregulation is the major preventable risk factor for leading causes of chronic disease-related deaths. More specifically, chronic obesity is correlated with adipocyte hypertrophy and hyperplasia, both of which may be circadianly regulated. All circadian clocks are cell-intrinsic, and circadian oscillators that are tissue-specific control metabolic homeostasis by fine-tuning nutrient utilization; adipose tissue responds to microenvironmental changes in a clock-dependent manner. Thermogenic adipocytes can redirect energy away from ATP production during nutrient excess by disrupting the electrochemical proton gradient, producing heat in a process called Non- Shivering Thermogenesis (NST). Thermogenic adipocytes are sometimes capable of cell- autonomously sensing ambient temperature and adopting a reversible thermogenic profile. The circadian clock's importance in this thermogenic plasticity is not well understood, nor the cellular decision to adopt this state. The objective of this work is to understand how circadian rhythms affect adipocyte biology, especially thermogenic plasticity. To delineate the relationship between the cellular circadian system and adipocyte biology in the absence of organismal cues, circadian output will be characterized in Specific Aim 1 by transcriptionally profiling in vitro differentiated adipocytes from inguinal adipose tissue over 3 circadian days with a 2-hour resolution via RNAseq. In this way I will determine what aspects of adipocyte biology and environmental stimuli can be influenced by time-of-day. Though multilocularity and mitochondrial abundance are not indicators of thermogenic potential per se, these two organelles are intricately involved in NST. To extend the hypothesis that thermogenic plasticity is clock-controlled, I will use quantitative fluorescence live cell microscopy to characterize lipid droplet and mitochondrial spatial patterning and thereby describe organelle morphology as a function of circadian time. In Specific Aim 2 I will determine the cell-autonomous clock’s role in heat production, the quintessential component of thermogenesis, using infrared thermal imaging to identify rhythms in heat production (1) during a state of decreased bioenergetic efficiency via uncoupling with BAM15 and (2) by suppressing UCP1 with purine nucleotides. The long-term goal of this proposal is to determine the clock’s role in regulating thermogenesis. Findings from this study will increase our understanding of clock- controlled energy metabolism and adipocyte dysfunction, advancing our understanding of the non-linear association between weight, energy expenditure and risk in chronic disease.

抽象的 代谢失调是慢性疾病主要原因的主要可预防危险因素 disease-related deaths.更具体地说，慢性肥胖与脂肪细胞肥大相关 和增生，这两者都可能受到昼夜节律的调节。 All circadian clocks are cell-intrinsic, 组织特异性的昼夜节律振荡器通过微调控制代谢稳态 nutrient utilization;脂肪组织对微环境变化的反应具有时钟依赖性 方式。产热脂肪细胞可以在营养期间将能量从 ATP 生产中转移出去 通过破坏电化学质子梯度来过量，在称为“非-”的过程中产生热量 Shivering Thermogenesis (NST).产热脂肪细胞有时能够细胞 自主感应环境温度并采用可逆生热曲线。这 生物钟在这种产热可塑性中的重要性尚不清楚，细胞也不清楚 decision to adopt this state.这项工作的目的是了解昼夜节律如何 影响脂肪细胞生物学，尤其是产热可塑性。 To delineate the relationship between 在没有生物线索、昼夜节律的情况下，细胞昼夜节律系统和脂肪细胞生物学 输出将在特定目标 1 中通过转录分析体外分化来表征 来自腹股沟脂肪组织的脂肪细胞超过 3 个昼夜节律，分辨率为 2 小时 RNA测序。通过这种方式，我将确定脂肪细胞生物学和环境刺激的哪些方面 can be influenced by time-of-day.尽管多室性和线粒体丰度并不 这两种细胞器本身就是产热潜力的指标，它们与 NST 有着复杂的关系。 为了扩展生热可塑性是受时钟控制的假设，我将使用定量 荧光活细胞显微镜表征脂滴和线粒体空间图案 从而将细胞器形态描述为昼夜节律时间的函数。 In Specific Aim 2 I 将决定细胞自主时钟在热量产生中的作用，这是典型的组成部分 产热过程中，使用红外热成像来识别产热节律 (1) 通过与 BAM15 解偶联和 (2) 通过抑制生物能效率降低的状态 UCP1 with purine nucleotides.该提案的长期目标是确定时钟的作用 in regulating thermogenesis.这项研究的结果将增加我们对时钟的理解 控制能量代谢和脂肪细胞功能障碍，增进我们对脂肪细胞的理解 体重、能量消耗和慢性病风险之间的非线性关联。