Li Ying, Tan YuanYuan, Zhao Zhao
College of Information Technology, Shanghai Ocean University, Shanghai 201306, China.
College of Information Technology, Shanghai Ocean University, Shanghai 201306, China.
Biosystems. 2024 Feb;236:105111. doi: 10.1016/j.biosystems.2023.105111. Epub 2023 Dec 29.
Circadian rhythm is an essential component of biology that organizes the internal synchrony of the organism in response to the environment. Aging significantly impacts circadian rhythm and is also associated with specific sleep complaints in mammals, including earlier awakening and decreased sleep consolidation at the end of the night. However, the regulation mechanism of aging on the circadian rhythm is far from clear. To further understand the impact of aging, we use an existing mathematical model of circadian rhythm combined with the aging system to explore the effects of aging on circadian rhythm and two kinds of sleep disorders, familial late sleep syndrome (FASPS) and delayed sleep syndrome (DSPS). We get a few intriguing findings from numerical simulations. Aging weakens rhythmicity by reducing the amplitude of circadian rhythm. Aging exacerbates the sleep pattern of being early to bed and early to rise by shortening the period of circadian rhythm and advancing the entrainment phase. Aging reduces the ability of the circadian rhythm to respond to light. The elderly need stronger light to get entrainment with the environmental light cycle. It is more difficult for the elderly to recover from disturbed light. Especially elderly people take a longer time to overcome jet lag. Aging worsens the "morningness" of FASPS disorder patients and improves the symptoms of DSPS disorder patients. This study helps to better understand the impacts of aging on circadian rhythm and sleep disorders and provides theoretical support for the treatment of circadian disorders in the elderly.
昼夜节律是生物学的一个重要组成部分，它使生物体的内部同步性与环境相适应。衰老会显著影响昼夜节律，并且在哺乳动物中还与特定的睡眠问题相关，包括早醒以及夜间睡眠巩固能力下降。然而，衰老对昼夜节律的调节机制尚不清楚。为了进一步了解衰老的影响，我们使用现有的昼夜节律数学模型结合衰老系统，来探究衰老对昼夜节律以及两种睡眠障碍——家族性晚睡综合征（FASPS）和睡眠时相延迟综合征（DSPS）的影响。我们从数值模拟中得到了一些有趣的发现。衰老通过降低昼夜节律的振幅来削弱节律性。衰老通过缩短昼夜节律的周期并提前同步相位，加剧早睡早起的睡眠模式。衰老降低了昼夜节律对光的反应能力。老年人需要更强的光线才能与环境光周期同步。老年人从光线干扰中恢复更困难。尤其是老年人克服时差需要更长时间。衰老会使FASPS障碍患者的“晨型”情况恶化，而改善DSPS障碍患者的症状。这项研究有助于更好地理解衰老对昼夜节律和睡眠障碍的影响，并为治疗老年人的昼夜节律紊乱提供理论支持。
