Bonmatí-Carrión María-Ángeles, Casado-Ramirez Elvira, Moreno-Casbas María-Teresa, Campos Manuel, Madrid Juan Antonio, Rol Maria-Angeles
Chronobiology Laboratory, Department of Physiology, College of Biology, University of Murcia, Mare Nostrum Campus, IUIE, IMIB-Arrixaca, 30100 Murcia, Spain.
Ciber Fragilidad y Envejecimiento Saludable (CIBERFES), 28029 Madrid, Spain.
Biology (Basel). 2022 Jul 28;11(8):1130. doi: 10.3390/biology11081130.
Human circadian rhythmicity is subjected to the internal circadian clock, the sun and social clocks (official time, social/work schedules). The discrepancy among these clocks, as occurs when official time does not match its geographical time zone, may produce circadian disruption. Western Spain (GMT+1/+2) and Portugal (GMT0/+1) share similar longitudes (sun time) but have different official times. This provides a unique opportunity to evaluate the effects of official time on circadian rhythmicity and sleep in elderly and retired populations (with no remunerated duties presumed, although other social commitments may be present) at both locations. Although both populations slept enough for their age (7-8 h), circadian robustness (e.g., interdaily stability, relative amplitude) was greater in Portugal, especially during weekdays, while greater desynchronization (both body temperature vs. motor activity and body temperature vs. light exposure) tended to occur in the Spaniards. Once corrected by GMT0, meals took place later in Spain than in Portugal, especially as the day progresses, and a possible interplay between bed/meal timings and internal desynchronization was found. Our results point to the possible deleterious effect on circadian system robustness when official time is misaligned with its geographical time zone.
人类的昼夜节律受到内部生物钟、太阳和社会时钟（官方时间、社交/工作时间表）的影响。当官方时间与其所在地理时区不匹配时，这些时钟之间就会出现差异，这可能会导致昼夜节律紊乱。西班牙西部（格林威治标准时间+1/+2）和葡萄牙（格林威治标准时间0/+1）经度相似（太阳时间），但官方时间不同。这提供了一个独特的机会，来评估官方时间对这两个地区老年人和退休人群（假定没有有偿工作，尽管可能存在其他社会活动）昼夜节律和睡眠的影响。尽管这两个人群的睡眠时间都符合其年龄阶段（7-8小时），但葡萄牙人的昼夜节律稳健性（例如，日间稳定性、相对振幅）更强，尤其是在工作日期间，而西班牙人则更容易出现更大程度的不同步（体温与运动活动之间以及体温与光照暴露之间）。一旦以格林威治标准时间0进行校正，西班牙的用餐时间比葡萄牙晚，尤其是随着一天的推进，并且发现就寝/用餐时间与内部不同步之间可能存在相互作用。我们的研究结果表明，当官方时间与其所在地理时区不一致时，可能会对昼夜节律系统的稳健性产生有害影响。
