Department of Otolaryngology, Medical School, University of Michigan, Ann Arbor, MI, USA.
J Dent Res. 2014 Jan;93(1):27-35. doi: 10.1177/0022034513505768. Epub 2013 Sep 24.
Most physiological processes in mammals display circadian rhythms that are driven by the endogenous circadian clock. This clock is comprised of a central component located in the hypothalamic suprachiasmatic nucleus and subordinate clocks in peripheral tissues. Circadian rhythms sustain 24-hour oscillations of a large number of master genes controlling the correct timing and synchronization of diverse physiological and metabolic processes within our bodies. This complex regulatory network provides an important communication link between our brain and several peripheral organs and tissues. At the molecular level, circadian oscillations of gene expression are regulated by a family of transcription factors called "clock genes". Dysregulation of clock gene expression results in diverse human pathological conditions, including autoimmune diseases and cancer. There is increasing evidence that the circadian clock affects tooth development, salivary gland and oral epithelium homeostasis, and saliva production. This review summarizes current knowledge of the roles of clock genes in the formation and maintenance of oral tissues, and discusses potential links between "oral clocks" and diseases such as head and neck cancer and Sjögren's syndrome.
哺乳动物的大多数生理过程都表现出昼夜节律，这些节律是由内源性生物钟驱动的。这个生物钟由位于下丘脑视交叉上核的中央组件和外周组织中的从属时钟组成。昼夜节律维持着大量主控基因的 24 小时波动，这些基因控制着我们体内各种生理和代谢过程的正确时间和同步性。这个复杂的调控网络为我们的大脑和几个外周器官和组织之间提供了一个重要的通讯联系。在分子水平上，基因表达的昼夜波动受称为“时钟基因”的一类转录因子调控。时钟基因表达的失调导致多种人类病理状况，包括自身免疫性疾病和癌症。越来越多的证据表明，生物钟会影响牙齿发育、唾液腺和口腔上皮组织稳态以及唾液分泌。这篇综述总结了时钟基因在口腔组织形成和维持中的作用的最新知识，并讨论了“口腔时钟”与头颈部癌症和干燥综合征等疾病之间的潜在联系。
