Shan Li-Na, Chai Wen-Shu, Lu Si-Jing, Song Yong-Gui, Su Dan, Yang Shuman, Shi Xian-Bao, Wang Wei
Department of Respiratory, The First Affiliated Hospital of Jinzhou Medical University, Jinzhou, Liaoning, 121001, China.
National Pharmaceutical Engineering Center for Solid Preparation in Chinese Herbal Medicine, Jiangxi University of Traditional Chinese Medicine, Nanchang, Jiangxi, 330004, China.
Biochem Biophys Res Commun. 2017 Jan 29;483(1):283-287. doi: 10.1016/j.bbrc.2016.12.151. Epub 2016 Dec 23.
Obstructive sleep apnea (OSA) is a common disorder characterized by chronic intermittent hypoxia (CIH). Excessive daytime sleepiness (EDS) is one of severe complications frequently associated with OSA. Lipocalin-type prostaglandin synthase (L-PGDS) is potentially responsible for the production of prostaglandin D (PGD) which is an endogenous sleep inducer. To date, whether the content of PGD and PGDS is related to intermittent hypoxia has never been reported. The aim of this study was to compare the content of PGD and L-PGDS in rats' brains with and without intermittent hypoxia. Adult male Wistar rats (n = 48; 8-10 weeks) were averagely divided into two groups. One was control group, and the other group was exposed to IH (12 h/day for 6 weeks). In each group there are four time-points including 0, 2, 4 and 6 weeks, and six rats were killed and studied at each time-point. At the end of 0, 2, 4 and 6 weeks, the concentrations of PGD in brains were measured by LC-MS/MS. In addition, the expressions of L-PGDS protein and mRNA in brains were investigated by western blotting and real-time polymerase chain reaction (RT-PCR), respectively. The results showed the concentrations of PGD in CIH rat brains were higher than those in control groups from the second week. At the end of 6 weeks, the concentrations of PGD in CIH and control groups were 11.1 and 5.9 ng/g, respectively. The levels of L-PGDS protein and mRNA followed the same trend during the whole 6 weeks. The results will provide a new idea to explore that patients with OSA are always accompanied by excessive daytime sleepiness.
阻塞性睡眠呼吸暂停（OSA）是一种以慢性间歇性缺氧（CIH）为特征的常见疾病。白天过度嗜睡（EDS）是与OSA经常相关的严重并发症之一。脂联素型前列腺素合酶（L-PGDS）可能负责前列腺素D（PGD）的产生，而PGD是一种内源性睡眠诱导剂。迄今为止，PGD和PGDS的含量是否与间歇性缺氧有关尚未见报道。本研究的目的是比较有或无间歇性缺氧的大鼠大脑中PGD和L-PGDS的含量。成年雄性Wistar大鼠（n = 48；8-10周）平均分为两组。一组为对照组，另一组暴露于间歇性缺氧（每天12小时，持续6周）。每组有四个时间点，包括0、2、4和6周，每个时间点处死6只大鼠并进行研究。在0、2、4和6周结束时，通过液相色谱-串联质谱法（LC-MS/MS）测量大脑中PGD的浓度。此外，分别通过蛋白质印迹法和实时聚合酶链反应（RT-PCR）研究大脑中L-PGDS蛋白和mRNA的表达。结果显示，从第二周起，CIH大鼠大脑中PGD的浓度高于对照组。在6周结束时，CIH组和对照组中PGD的浓度分别为11.1和5.9 ng/g。在整个6周内，L-PGDS蛋白和mRNA的水平呈现相同趋势。这些结果将为探索OSA患者总是伴有白天过度嗜睡提供新思路。
