RAHN AG, Dörflistrasse 120, Zürich, 8050, Switzerland.
Int J Cosmet Sci. 2020 Aug;42(4):313-319. doi: 10.1111/ics.12623. Epub 2020 Jun 5.
The circadian rhythm was set into focus by awarding the Nobel Price of Physiology/Medicine to Jeffrey Hall, Michael Rosbash and Michael Young in late 2017. Numerous publications elucidated the molecular mechanisms driving the circadian biorhythms of our body, peripheral organs and each single cell. However, there is minor knowledge on the circadian rhythm of the skin, which has its own peripheral circadian clock in contact with cosmetic formulations. The skin's epidermal clock is excessively influenced by environmental factors like UV radiation or modern lifestyle, which may induce epidermal jetlag. Here, we give an overview on the current knowledge about the epidermal circadian clock and provide a cosmetic solution to protect and preserve the biorhythm of the skin.
Quantitative RT-PCR to analyse the gene expression of circadian clock genes and the downstream DNA repair gene OGG1 in keratinocytes irradiated with UV-B. In vivo study to determine skin parameters dependent on the circadian cycle and interference of cosmetic formulations to them by assessment of morning and evening values at each measurement day after 28, 56 and 84 days of the study.
UV-B irradiation leads to a pronounced delay in circadian clock and downstream gene expression which interferes in the proper function of epidermal stem cells and as thus skin function. The use of a cosmetic active ingredient prevents cyclobutane pyrimidine dimer formation, protects epidermal stem cells and resets the circadian gene expression. It preserves the circadian changes in skin hydration, reduces daily fluctuations of skin redness and strengthens the skin barrier.
The skin has its own circadian biorhythm to gain full functionality. Interruption of this oscillation will lead to functional impairments. Here we show a cosmetic solution to protect and preserve the skin's circadian rhythm. DNA protection, ROS elimination and stimulation of circadian gene expression seem to be crucial to keep the skin in balance.
2017 年底，诺贝尔生理学或医学奖授予杰弗里·霍尔、迈克尔·罗斯巴什和迈克尔·杨，生物钟研究由此成为焦点。大量文献阐明了驱动我们身体、外周器官和每个单个细胞的生物钟生物节律的分子机制。然而，人们对皮肤的生物钟知之甚少，皮肤有自己的外周生物钟与化妆品配方接触。皮肤的表皮时钟受到环境因素（如紫外线辐射或现代生活方式）的过度影响，这可能会导致表皮时差。在这里，我们概述了目前关于表皮生物钟的知识，并提供了一种保护和维持皮肤生物节律的化妆品解决方案。
采用定量 RT-PCR 分析经 UV-B 照射的角质形成细胞中生物钟基因和下游 DNA 修复基因 OGG1 的基因表达。在体内研究中，通过评估每个测量日的早晨和晚上值，确定依赖于生物钟周期的皮肤参数，并在研究的第 28、56 和 84 天评估化妆品配方对其的干扰。
UV-B 照射导致生物钟和下游基因表达明显延迟，这会干扰表皮干细胞的正常功能，从而影响皮肤功能。使用化妆品活性成分可以防止环丁烷嘧啶二聚体的形成，保护表皮干细胞并重置生物钟基因表达。它可以保持皮肤水合作用的昼夜变化，减少皮肤发红的日常波动，并增强皮肤屏障。
皮肤有自己的生物钟生物节律以获得充分的功能。这种振荡的中断会导致功能障碍。在这里，我们展示了一种保护和维持皮肤生物钟的化妆品解决方案。DNA 保护、ROS 消除和生物钟基因表达的刺激似乎对于保持皮肤平衡至关重要。
