美国一项最新研究发现，生物钟与血糖调节密切相关。科研人员说，这一发现将有助于更好地帮助调节人体血糖水平。
美国加州大学医学院的科研人员在新一期《国家科学院学报》上发表文章说，他们对实验鼠以及人类干细胞进行试验时发现，在糖皮质激素作用下，有三个已知可以控制生物钟的基因改变了自身的活性。进一步的研究发现，上述基因活性的改变直接与血糖水平调节相关。
参与这项研究的布赖恩·费尔德曼博士指出，他们的发现表明，生物体内糖皮质激素的日常变化，与人体的生物钟以及血糖水平密切相关。而一些含有糖皮质激素的常用药物，被较为广泛地用于治疗重度哮喘以及癌症等，这就导致患者可能因糖皮质激素的作用而出现糖尿病这样的副作用。
费尔德曼说，新发现将有助于医生考虑如何配合人体生物钟的节奏而正确使用相关药物。例如，按照人体生物钟的规律使用糖皮质激素药物，就能有效减小对血糖水平的干扰；而对于那些已经患有糖尿病的患者，也可考虑运用上述发现采用药物来干预其体内血糖水平的调节。(生物谷Bioon.com)
生物谷推荐原始出处：
PNAS October 5, 2009, doi: 10.1073/pnas.0909733106
Glucocorticoid regulation of the circadian clock modulates glucose homeostasis
Alex Y.-L. Soa,b, Teresita U. Bernala,b, Marlisa L. Pillsburyb, Keith R. Yamamotob,1 and Brian J. Feldmana,b,2
aDepartment of Pediatrics, University of California, 513 Parnassus Drive, San Francisco, CA 94143; and
bDepartment of Cellular and Molecular Pharmacology, University of California, 600 16th Street, S-222, San Francisco, CA 94158-2280
Circadian clock genes are regulated by glucocorticoids; however, whether this regulation is a direct or secondary effect and the physiological consequences of this regulation were unknown. Here, we identified glucocorticoid response elements (GREs) at multiple clock genes and showed that 3 were directly regulated by the glucocorticoid receptor. We determined that a GRE within the core clock gene Per2 was continuously occupied during rhythmic expression and essential for glucocorticoid regulation of that gene in vivo. We further demonstrated that mice with a genomic deletion spanning this GRE expressed elevated leptin levels and were protected from glucose intolerance and insulin resistance on glucocorticoid treatment but not from muscle wasting. We conclude that Per2 is an integral component of a particular glucocorticoid regulatory pathway and that glucocorticoid regulation of the peripheral clock is selectively required for some actions of glucocorticoids.
