For several years, a great effort has been devoted to understand how circadian oscillations in physiological processes are determined by the circadian clock system. This system is composed by the master clock at the suprachiasmatic nucleus which sets the pace and tunes peripheral clocks in several organs. It was recently demonstrated that the choroid plexus epithelial cells that compose the blood-cerebrospinal fluid barrier hold a circadian clock which might control their multiple functions with implications for the maintenance of brain homeostasis. However, the choroid plexus activities regulated by its inner clock are still largely unknown. In this review, we propose that several choroid plexus functions might be regulated by the circadian clock, alike in other tissues. We provide evidences that the timing of cerebrospinal fluid secretion, clearance of amyloid-beta peptides and xenobiotics, and the barrier function of the blood-cerebrospinal fluid barrier are regulated by the circadian clock. These data, highlight that the circadian regulation of the blood-cerebrospinal fluid barrier must be taken into consideration for enhancing drug delivery to central nervous system disorders.

几年来，人们一直致力于了解生理过程中的昼夜节律振荡是如何由生物钟系统决定的。该系统由视交叉上核的主时钟组成，它设定步调并调整多个器官的外围时钟。最近的研究表明，构成血脑脊液屏障的脉络丛上皮细胞拥有一个生物钟，该生物钟可能控制它们的多种功能，这对维持脑内稳态具有重要意义。然而，由其内部时钟调节的脉络丛活动仍然很大程度上未知。在这篇综述中，我们提出几种脉络丛功能可能受到生物钟的调节，就像在其他组织中一样。我们提供的证据表明脑脊液分泌的时间，β-淀粉样蛋白肽和异生物质的清除以及血脑脊液屏障的屏障功能受生物钟调节。这些数据突出表明，必须考虑血脑脊液屏障的昼夜节律调节，以增强对中枢神经系统疾病的药物输送。