PHOTOPERIODIC CONTROL OF OBESITY

光周期控制肥胖

• 批准号: 3233531
• 负责人: Timothy Jon Bartness
• 金额: $ 3.55万
• 依托单位: GEORGIA STATE UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 1988
• 资助国家: 美国
• 起止时间: 1988-09-01 至 1991-11-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/3233531
• 关键词: adipose tissue; bioenergetics; body composition; brown fat; circadian rhythms; glucocorticoids; hamsters; insulin; lipid biosynthesis; lipid metabolism; lipolysis; melatonin; neuroendocrine system; obesity; pineal body; seasons; sympathetic nervous system; thyroid hormones; thyroidectomy

The goal of these experiments is to determine the critical factors involved in the photoperiodic control of seasonal changes in body and lipid mass, metabolism, and energy expenditure in hamsters. The seasonal changes in body weight in Syrian (Mesocricetus auratus) and Siberian (Phodopus sungorus sungorus) hamsters are reflected entirely as changes in carcass lipid. These naturally- occurring changes in lipid mass are interesting in these animals because, although both species show the same seasonal reproductive responses, they show opposite changes in body weight and fat to the same environmental stimulus (daylength), mediated by the same neuroendocrine transducer (pineal gland and its hormone, melatonin). Three sets of experiments are proposed. The first set of experiments will describe the seasonal changes in lipid metabolism and their underlying mechanisms, and include measures of regional changes in white and brown adipose tissue lipogenesis and lipolysis, and the involvement of the sympathetic nervous system in these processes. The second set of experiments will examine the "regulation" of body weight, lipid mass and metabolism in Siberian hamsters, in particular the recovery of body and lipid mass, and adipose tissue cellularity changes following starvation-induced decreases in body weight, and the surgical removal of adipose tissue (lipectomy) performed during both the weight gain and loss phases of the body weight cycle. The third set of experiments will explore the possibility that melatonin directly affects hamster fat cell metabolism and that "secondary hormones" that are altered by the photoperiod (melatonin), in turn affect body and lipid mass changes due to changes in the daylength. Photoperiod induced changes in insulin, glucocorticoids and thyroid hormones will be documented, and experimentally manipulated to mimic the circulating levels associated with the photoperiod opposite to the photoperiod the animals are housed in. Changes in lipid mass and metabolism will be monitored. This multidisciplinary approach (utilizing concepts and techniques from endocrinology, biochemistry, neurosciences, zoology and psychobiology) should provide new information about the seasonal influences on body weight, fat, and lipid metabolism that may reflect fundamental processes in the development, maintenance and reversal of obesity.

这些实验的目的是确定关键因素 参与身体季节性变化的光周期控制 以及仓鼠的脂质质量，代谢和能量消耗。 叙利亚体重的季节性变化（Mesocricetus Auratus）和西伯利亚（Phodopus sungorus sungorus）仓鼠 完全反射为car体脂质的变化。 这些自然 - 这些动物的脂质质量变化很有趣 因为，尽管两种物种都显示出同一季节性 生殖反应，它们显示出相反的身体变化 重量和脂肪到相同的环境刺激（日长）， 由相同的神经内分泌传感器介导（松果体和 它的激素，褪黑激素）。 提出了三组实验。 第一组实验将描述 脂质代谢及其基本机制，包括 白色和棕色脂肪组织的区域变化的度量 脂肪生成和脂解，以及交感神经的参与 这些过程中的神经系统。 第二组实验将检查 西伯利亚仓鼠的体重，脂质质量和代谢 特别是身体和脂质质量的恢复，以及脂肪组织 饥饿引起的体内降低后的细胞变化 重量，脂肪组织的手术去除（脂肪切除术） 在体重增加和体重损失阶段进行 重量周期。 第三组实验将探讨 褪黑激素直接影响仓鼠脂肪细胞代谢，并且 被光周期改变的“次级激素” （褪黑激素），进而影响身体和脂质质量的变化 日程变化。 光周期引起的胰岛素变化， 将记录糖皮质激素和甲状腺激素，并 通过实验操纵以模仿循环水平 与光周期相反的光周期相关 动物被安置在脂质质量和代谢的变化中 被监视。 这种多学科的方法（利用概念和技术 来自内分泌学，生物化学，神经科学，动物学和 心理生物学）应提供有关季节性的新信息 影响体重，脂肪和脂质代谢的影响 反映开发，维护的基本过程 和肥胖的逆转。