Ruiter Marieke, Buijs Ruud M, Kalsbeek Andries
Netherlands Institute for Neuroscieces, Hypothalamic Intergration Mechanism Group, Amsterdam, The Netherlands.
Curr Diabetes Rev. 2006 May;2(2):213-26. doi: 10.2174/157339906776818596.
Glucose is one of the most important energy sources for the body in general, and the brain in particular. It is essential for survival to keep glucose levels within strict boundaries. Acute disturbances of glucose homeostasis are rapidly corrected by hormonal and neuronal mechanisms. Furthermore, changes in energy expenditure associated with the light-dark cycle induce variations in the plasma glucose concentration that are more gradual. Organisms take advantage of adapting their internal physiology to the predictable daily changes in energy expenditure, because it enables them to anticipate these changes and to prevent unnecessary disturbance of homeostasis. The hypothalamic biological clock, located in the suprachiasmatic nucleus (SCN), receives light information from the eyes and transmits this information to the rest of the body to synchronize physiology to the environment. Here we review several studies providing evidence for biological clock control of the daily variation in several aspects of glucose metabolism. Although both hormones and the autonomic nervous system can stimulate glucose uptake or production by organs in the periphery, we have shown that the biological clock control of glucose metabolism mostly occurs through the autonomic nervous system. The critical involvement of the biological clock is also indicated by several studies, indicating that disturbance of the biological clock is often associated with metabolic diseases, such as obesity, diabetes mellitus and hypertension.
一般而言，葡萄糖是身体最重要的能量来源之一，对大脑来说尤其如此。将葡萄糖水平维持在严格的范围内对生存至关重要。葡萄糖稳态的急性紊乱会通过激素和神经元机制迅速得到纠正。此外，与昼夜明暗周期相关的能量消耗变化会导致血浆葡萄糖浓度更缓慢的变化。生物体利用自身内部生理机能适应能量消耗的可预测的每日变化，因为这使它们能够预测这些变化并防止内环境稳态受到不必要的干扰。位于视交叉上核（SCN）的下丘脑生物钟接收来自眼睛的光信息，并将此信息传递给身体的其他部位，以使生理机能与环境同步。在此，我们综述了多项研究，这些研究为生物钟控制葡萄糖代谢多个方面的每日变化提供了证据。尽管激素和自主神经系统都可以刺激外周器官摄取或产生葡萄糖，但我们已经表明，生物钟对葡萄糖代谢的控制主要通过自主神经系统发生。多项研究也表明了生物钟的关键作用，这些研究表明生物钟紊乱通常与肥胖、糖尿病和高血压等代谢疾病有关。
