Sleep and Circadian Rhythms in Tuberous Sclerosis Complex

描述（申请人提供）：睡眠是一种普遍存在但神秘的动物行为。越来越多的证据表明，正常睡眠在健康和疾病中起着至关重要的作用。对于患有神经发育障碍的儿童，如多发性硬化症（TSC），尤其如此。TSC是一种神经遗传综合征，由Tsc 1或Tsc 2基因突变引起，可导致癫痫、智力残疾和自闭症。据报道，50-90%的TSC儿童存在睡眠功能障碍，并对日间行为、癫痫控制、代谢稳态和心理健康产生不利影响。TSC和其他神经发育综合征中睡眠障碍的治疗受到限制，因为对这些条件下睡眠功能障碍的机制基础缺乏了解。由Tsc 1和Tsc 2编码的蛋白质抑制哺乳动物雷帕霉素靶蛋白（mTOR）的功能，mTOR是所有细胞中营养状态和粘附的保守和关键整合剂。Lipton博士使用TSC的小鼠模型来建立TSC的原因与基本生物钟蛋白BMAL 1之间的机制联系。这些发现导致了Tsc/mTOR通路对大脑中的中央计时机制（下丘脑的视交叉上核（SCN））的功能至关重要的假设。为了验证这一假设，目前的指导训练计划有以下目标：（1）确定Tsc/mTOR信号在大脑的中央计时器-视交叉上核（SCN）中的必要性和充分性;（2）证明Tsc/mTOR/S6 K1介导的关键时钟蛋白BMAL 1磷酸化的体内生理需求;（3）确定TSC 1/2在睡眠维持和稳态中的作用。这些研究将确立Tsc/mTOR通路在调节睡眠和昼夜节律中的分子作用。这些研究将在哈佛医学院赞助下的波士顿儿童医院和Beth-Israel Deaconess医疗中心进行，由著名睡眠科学家和神经解剖学家Clifford Saper博士和儿童神经学家Mustafa Sahin博士共同指导。在Charles Czeisler博士的指导下，哈佛睡眠医学部为最高水平的睡眠科学和医学的多学科，跨机构学术培训提供了肥沃的环境。Lipton博士是一名儿童神经学家和睡眠专家，其职业目标是成为一名独立的医生-科学家，致力于了解睡眠和昼夜节律在神经发育障碍中的作用。这个指导奖将为Lipton博士提供实验设计和实践，教学法和数据分析方面的结构化培训经验，这将极大地促进向独立医生-科学家职业生涯的过渡。 公共卫生相关性：项目叙事睡眠已成为人类健康的一个关键变量。睡眠功能障碍会对日间行为、癫痫控制和代谢参数产生不利影响，因此对神经发育障碍儿童尤为重要。本研究旨在探讨神经发育障碍性硬化症小鼠模型中睡眠和昼夜节律功能障碍的生物学机制。这项工作的目标是确定合理的治疗目标，将改善睡眠功能障碍，伴随着发育中的大脑和调节睡眠和昼夜节律的基本机制的障碍。

DESCRIPTION (provided by applicant): Sleep is a ubiquitous yet mysterious animal behavior. Mounting evidence points to a crucial role for normal sleep in health and disease. This may be especially true for children with neurodevelopmental disorders such as Tuberous Sclerosis Complex (TSC). TSC is a neurogenetic syndrome that results from mutations in either the Tsc1 or Tsc2 genes that cause epilepsy, intellectual disability, and autism. Sleep dysfunction is reported in 50-90% of children with TSC and adversely affects daytime behavior, seizure control, metabolic homeostasis and psychological well- being. Treatment of sleep disorders in TSC and other neurodevelopmental syndromes has been limited by a fundamental lack of understanding of the mechanistic underpinnings of sleep dysfunction in these conditions. The proteins encoded by Tsc1 and Tsc2 inhibit the function of the mammalian target of rapamycin (mTOR), a conserved and critical integrator of nutrient status and anabolism in all cells. Dr. Lipton has used mouse models for TSC to establish a mechanistic link between the causes of TSC and the essential circadian clock protein BMAL1. These findings lead to the hypothesis that the Tsc/mTOR pathway is critical to the function of the central timekeeping mechanism in the brain, the suprachiasmatic nucleus of the hypothalamus (SCN). To test this hypothesis, the current mentored training plan has the following aims: (1) Determine the necessity and sufficiency of Tsc/mTOR signaling in the brain's central timekeeper, the suprachiasmatic nucleus (SCN); (2) Demonstrate the physiological requirement for Tsc/mTOR/S6K1-mediated phosphorylation of the crucial clock protein BMAL1 in vivo; (3) Determine the roles of TSC1/2 in sleep maintenance and homeostasis. These studies will establish the molecular role of the Tsc/mTOR pathway in the regulation of sleep and circadian rhythms. These studies will be carried at Children's Hospital Boston and Beth-Israel Deaconess Medical Center within the auspices of Harvard Medical School, under the dual mentorship of Dr. Clifford Saper, a renowned sleep scientist and neuroanatomist, and Dr. Mustafa Sahin, a child neurologist and pioneer in the understanding of the neurological basis for TSC. The Harvard Division of Sleep Medicine under the direction of Dr. Charles Czeisler provides a fertile environment for multi-disciplinary, cross-institutional academic training in sleep science and medicine at the highest level. Dr. Lipton is a child neurologist and sleep specialist with the career goal of becoming an independent physician-scientist committed to understanding the role of sleep and circadian rhythms in neurodevelopmental disorders. This mentored award will provide Dr. Lipton the structured training experience in experimental design and practice, didactics, and data analysis that will greatly facilitate the transition to a career as an independent physician-scientist. PUBLIC HEALTH RELEVANCE: Project Narrative Sleep has emerged as a critical variable in human health. Sleep dysfunction adversely affects daytime behavior, seizure control, and metabolic parameters and is therefore of particular importance to children with neurodevelopmental disorders. This proposal investigates the biological mechanisms of sleep and circadian dysfunction in mouse models of the neurodevelopmental disorder Tuberous Sclerosis Complex. The goal of this work is to identify rational therapeutic targets that would ameliorate sleep dysfunction that accompany disorders of the developing brain and to fundamental mechanisms that regulate sleep and circadian rhythms.