Nicolaides Nicolas C, Chrousos George P
Division of Endocrinology, Metabolism and Diabetes, First Department of Pediatrics, National and Kapodistrian University of Athens Medical School, "Aghia Sophia" Children's Hospital, Athens, Greece.
Division of Endocrinology and Metabolism, Center of Clinical, Experimental Surgery and Translational Research, Biomedical Research Foundation of the Academy of Athens, Athens, Greece.
Eur J Neurosci. 2020 Jul;52(1):2575-2585. doi: 10.1111/ejn.14692. Epub 2020 Feb 28.
Organisms have developed a highly conserved and tightly regulated circadian system, to adjust their daily activities to day/night cycles. This system consists of a central clock, which is located in the hypothalamic suprachiasmatic nucleus, and the peripheral clocks that are ubiquitously expressed in all tissues. Both the central and peripheral clocks communicate with each other and achieve circadian oscillations of gene expression through transcriptional/translational loops mediated by clock transcription factors. It is worth mentioning that circadian non-transcriptional/non-translational rhythms also occur in non-nucleated cells. Interestingly, sex has been identified as an important factor influencing the activity of the circadian system. Indeed, several sex differences have been documented in the anatomy, physiology and pathophysiology that pertain to circadian rhythms. In this review, we present the historical milestones of understanding circadian rhythms, describe the central and peripheral components of the circadian clock system, discuss representative examples of sexual dimorphism of circadian rhythms, and present the most relevant clinical implications.
生物体已经发展出一种高度保守且严格调控的昼夜节律系统，以使其日常活动与昼夜周期相适应。该系统由位于下丘脑视交叉上核的中央时钟和在所有组织中普遍表达的外周时钟组成。中央时钟和外周时钟相互通信，并通过由时钟转录因子介导的转录/翻译反馈环实现基因表达的昼夜节律振荡。值得一提的是，昼夜非转录/非翻译节律也发生在无核细胞中。有趣的是，性别已被确定为影响昼夜节律系统活动的一个重要因素。事实上，在与昼夜节律相关的解剖学、生理学和病理生理学方面已经记录了一些性别差异。在这篇综述中，我们介绍了理解昼夜节律的历史里程碑，描述了昼夜节律时钟系统的中央和外周组成部分，讨论了昼夜节律性二态性的代表性例子，并介绍了最相关的临床意义。
