PPARG regulates osteocyte bioenergetics and function during aging

PPARG 在衰老过程中调节骨细胞生物能和功能

基本信息

批准号：
10634739
负责人：
Patrick Robert Griffin
金额：
$ 66.56万
依托单位：
UNIVERSITY OF TOLEDO HEALTH SCI CAMPUS
依托单位国家：
美国
项目类别：
财政年份：
2021
资助国家：
美国
起止时间：
2021-09-30 至 2026-05-31
项目状态：
未结题

来源：
https://reporter.nih.gov/project-details/10634739
关键词：
Adipocytes Affect Age-Related Bone Loss Aging Agonist American Applications Grants Bioenergetics Bone Formation Inhibition Bone Resorption Bone remodeling C57BL/6 Mouse CRISPR/Cas technology Cell physiology Cells Chronic Disease Coculture Techniques Diabetes Mellitus Diagnosis Disease Elderly Endocrine Energy Metabolism Enhancers Exhibits Fracture Genetic Genetic Transcription Homeostasis Hormonal Hyperglycemia Impairment In Vitro Knowledge Lead Maintenance Metabolic Diseases Metabolic dysfunction Metabolism Mitochondria Molecular Mus Nuclear Receptors Organ Organ Culture Techniques Osteoblasts Osteoclasts Osteocytes Osteogenesis Osteoporosis PPAR gamma Pathway interactions Physiologic calcification Population Process Production Proteins Proteomics Quality of life Regulation Research Role Signal Transduction Skeleton TNFSF11 gene Testing aged aging population bone bone cell bone loss bone mass bone metabolism bone quality effective therapy experimental study improved in vivo Model inhibitor insight mouse model novel osteoblast differentiation paracrine pharmacologic preference programs promoter protein complex response rosiglitazone skeletal transcriptomics

项目摘要

Bone loss and impairment in energy metabolism with aging prevalently lead to fractures and diabetes. As an organ, the skeleton is one of the largest consumers of energy needed for bone remodeling and maintenance of bone homeostasis. Bone remodeling is under control of osteocytes, which constitute 90-95% of bone cells, and which bioenergetic program is largely unknown. New evidence indicates that nuclear receptor PPARG, which is a global regulator of energy metabolism and pharmacological target to treat hyperglycemia, regulates osteocyte energy metabolism and their function including production of sclerostin, an inhibitor of WNT pathway activity and a key protein regulating bone remodeling. Research proposed in this application will provide an insight into the connection between osteocyte bioenergetics, its function in bone metabolism and systemic energy metabolism, and whether bone acts as the body “energostat” via osteocyte endocrine activities. The leading hypothesis is that changes in PPARG activity with aging alter osteocyte function and bioenergetics resulting in simultaneous decrease in bone formation and decrease in energy metabolism. This hypothesis will be tested in three specific aims. Aim 1 will determine how fuel choice and aging affect osteocyte function and whether these processes are PPARG dependent. With the use of aged C57BL/6 and γOTKO mice, bone organ cultures, and osteocyte-like MLO-Y4 cells with down-regulated PPARG, in combination with transcriptomics, quantitative proteomics, and coculture experiments, PPARG contribution to osteocyte aging will be defined. Aim 2 will contrast the PPARG protein interactome of osteocytes with the interactome of adipocytes, in response to either full agonist rosiglitazone or the inverse agonist SR10171, in order to define an optimal PPARG modulator for its beneficial effects on bone and metabolism. The analysis will be done on osteocyte- like MLO-Y4 cells using quantitative Tandem Mass Tag Proteomics. Aim 3 will define dynamics of PPARG interactome on PPRE sequences present in Sost promoter as a function of aging and in response to pharmacological modulation of PPARG activity. The premise of this application is to set a stage for precise pharmacologic manipulation with PPARG activities in osteocytes to simultaneously improve skeletal and metabolic dysfunction in elderly.

随着年龄的增长，骨质流失和能量代谢受损通常会导致骨折和糖尿病。作为器官，骨骼是骨骼重塑和维持骨骼所需能量的最大消耗者之一骨稳态是由骨细胞控制的，骨细胞占骨细胞的 90-95%，新的证据表明核受体 PPARG 的生物能程序在很大程度上是未知的。是能量代谢的全球调节剂和治疗高血糖的药理靶标，调节骨细胞能量代谢及其功能，包括产生硬化蛋白（WNT 通路抑制剂）本申请中提出的研究将提供一种调节骨重塑的活性和关键蛋白质。深入了解骨细胞生物能量学及其在骨代谢和全身功能中的功能之间的联系能量代谢，以及骨骼是否通过骨细胞内分泌活动充当身体的“能量抑制剂”。主要假设是 PPARG 活性随年龄的变化会改变骨细胞功能和生物能学导致骨形成同时减少和能量代谢减少。在三个具体目标中进行测试，目标 1 将确定燃料选择和老化如何影响骨细胞功能和这些过程是否依赖于 PPARG 通过使用老年 C57BL/6 和 γOTKO 小鼠，骨器官。培养物和 PPARG 下调的骨细胞样 MLO-Y4 细胞，结合转录组学，定量蛋白质组学和共培养实验将确定 PPARG 对骨细胞衰老的贡献。目标 2 将骨细胞的 PPARG 蛋白相互作用组与脂肪细胞的相互作用组进行对比，对完全激动剂罗格列酮或反向激动剂 SR10171 的反应，以确定最佳 PPARG 调节剂对骨骼和新陈代谢的有益影响将针对骨细胞进行分析。像 MLO-Y4 细胞一样，使用串联质量标签蛋白质组学 Aim 3 将定义 PPARG 的定量动力学。 Sost 启动子中存在的 PPRE 序列上的相互作用组作为衰老的函数并响应 PPARG 活性的药理调节是本申请的前提。利用骨细胞中的 PPARG 活性进行药理操作，同时改善骨骼和老年人代谢功能障碍。