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 代谢失调是导致慢性原因的主要可预防风险因素 与疾病有关的死亡。更具体地，慢性肥胖与脂肪细胞肥大相关 和增生，两者都可以受到循环的调节。所有昼夜节律都是细胞中的， 通过微调，是组织特异性控制代谢稳态的昼夜节律振荡器 营养利用；脂肪组织对时钟依赖性微环境变化的反应 方式。热脂肪细胞可以在养分期间将能量转移到ATP的产生中 通过破坏电化学质子梯度的过量，在称为非 - 的过程中产生热量 发抖的生热（NST）。热脂肪细胞有时能够细胞 自主感应环境温度并采用可逆的热谱。这 昼夜节律时钟在这种热可塑性中的重要性尚不清楚，也没有细胞 决定采用这种状态。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，尤其是热可塑性。描述 在没有有机线索的情况下 输出将在特定目标1中通过体外分化的转录分析来表征 腹股沟脂肪组织的脂肪细胞在3个昼夜节日中，分辨率为2小时 rnaseq。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 可能会受到时间的影响。虽然多界面和线粒体丰度不是 热潜能的指标本身，这两个细胞器复杂地参与NST。 为了扩大了热可塑性是时钟控制的假设，我将使用定量 荧光活细胞显微镜表征脂质液滴和线粒体空间图案 从而将细胞器的形态描述为昼夜节律的函数。在特定的目标2 i 将确定细胞自主时钟在热量产生中的作用，即典型的成分 热生成，使用红外热成像在热产生中识别节奏（1） 通过与BAM15解偶联的生物能效率降低的状态和（2）通过抑制 UCP1与嘌呤核苷酸。该提议的长期目标是确定时钟的角色 在控制热发生时。这项研究的发现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，促进我们对 体重，能量消耗和慢性疾病风险之间的非线性关联。