一份报告说，人类睡眠和觉醒的周期可能被记录在了一些被拔下来的头发的根部附着的细胞中。Makoto Akashi及其同事把4位受试者的睡眠与觉醒的模式与从受试者的头皮或胡须上拔下的细胞中的基因表达水平进行了比较，从而测试人类毛囊细胞中的生物钟基因表达是否反映了一个人的昼夜节律。这组科学家观察到受试者觉醒期间基因表达达到了峰值，而且那些昼夜节律基因表达阶段出现最早的受试者也在早晨醒来得最早。
实地测试表明倒班工人的昼夜节律滞后于他们的生活方式大约5小时，这提示倒班工人可能在一种长期的“时差感”状态下工作。这组作者说，尽管昼夜节律生物钟基因早在10多年前就被发现了，科学家此前尚未发现一种简单而准确的探测人类生物钟基因表达的方法。这组作者提出，非侵害性的人类毛囊活检可能有助于科学家研究和治疗睡眠障碍以及与昼夜节律生物钟机能障碍有关的其他疾病的患者。
生物谷推荐原文出处：
PNAS doi: 10.1073/pnas.1003878107
Noninvasive method for assessing the human circadian clock using hair follicle cells
Makoto Akashi a , 1 , Haruhiko Soma b , Takuro Yamamoto b , Asuka Tsugitomi c , Shiko Yamashita b , Takuya Yamamoto d , Eisuke Nishida d , Akio Yasuda b , James K. Liao e , and Koichi Node c
aResearch Institute for Time Studies, Yamaguchi University, Yamaguchi 753-8511, Japan;
bLife Science Laboratory, Advanced Materials Laboratories, Sony Corporation, 5-1-12 Kitashinagawa, Shinagawa-ku, Tokyo, 141-0001, Japan;
cDepartment of Cardiovascular and Renal Medicine, Saga University Faculty of Medicine, Saga 849-8501, Japan;
dDepartment of Cell and Developmental Biology, Graduate School of Biostudies, Kyoto University, Kyoto 606-8502, Japan; and
eVascular Medicine Research, Brigham and Women's Hospital, Cambridge, MA 02139
A thorough understanding of the circadian clock requires qualitative evaluation of circadian clock gene expression. Thus far, no simple and effective method for detecting human clock gene expression has become available. This limitation has greatly hampered our understanding of human circadian rhythm. Here we report a convenient, reliable, and less invasive method for detecting human clock gene expression using biopsy samples of hair follicle cells from the head or chin. We show that the circadian phase of clock gene expression in hair follicle cells accurately reflects that of individual behavioral rhythms, demonstrating that this strategy is appropriate for evaluating the human peripheral circadian clock. Furthermore, using this method, we indicate that rotating shift workers suffer from a serious time lag between circadian gene expression rhythms and lifestyle. Qualitative evaluation of clock gene expression in hair follicle cells, therefore, may be an effective approach for studying the human circadian clock in the clinical setting.
