Tam Charmaine S, Wong Melanie, Tam Kimberley, Aouad Leyla, Waters Karen A
The Children Hospital at Westmead, Sydney, NSW Australia.
Sleep. 2007 Jun;30(6):723-7. doi: 10.1093/sleep/30.6.723.
Obstructive sleep apnea (OSA) is characterized by repeated episodes of upper-airway obstruction during sleep leading to significant hypercapnic hypoxic conditions. These conditions are associated with increased levels of proinflammatory cytokines (including interleukin [IL]-6, tumor necrosis factor [TNF]-alpha, and C-reactive protein [CRP]) and subsequent increased cardiovascular risk. It is unclear whether hypercapnic hypoxia itself causes inflammatory perturbations.
We evaluated circulating IL-6, TNF- a and CRP in a piglet model of infant OSA, following exposure to acute intermittent hypercapnic hypoxia (IHH). Study groups comprised of treatment (n = 8) and control (n = 8) groups. Treatment was two 90-minute sessions of IHH with arterial blood sampled before and after each IHH session.
IL-6, TNF-alpha and CRP levels were measured before and after IHH treatment sessions. Results showed an increase in IL-6 following the first session of IHH that was neither sustained, nor repeated, during a subsequent exposure. Using mixed-modelling, TNF-alpha changed between time points and groups. There were no changes in CRP over the duration of the study.
These results suggest that acute hypoxia causes a transient increase in IL-6 levels and has implications for the pathogenesis of increased cardiovascular disease in OSA, especially in childhood.
阻塞性睡眠呼吸暂停（OSA）的特征是睡眠期间上呼吸道反复阻塞，导致严重的高碳酸血症性缺氧状况。这些状况与促炎细胞因子（包括白细胞介素[IL]-6、肿瘤坏死因子[TNF]-α和C反应蛋白[CRP]）水平升高以及随后心血管风险增加有关。尚不清楚高碳酸血症性缺氧本身是否会引起炎症紊乱。
我们在婴儿OSA的仔猪模型中，在暴露于急性间歇性高碳酸血症性缺氧（IHH）后，评估循环中的IL-6、TNF-α和CRP。研究组包括治疗组（n = 8）和对照组（n = 8）。治疗为两个90分钟的IHH疗程，在每个IHH疗程前后采集动脉血样。
在IHH治疗疗程前后测量IL-6、TNF-α和CRP水平。结果显示，在第一次IHH疗程后IL-6增加，但在随后的暴露中既未持续也未重复。使用混合模型分析，TNF-α在时间点和组之间有所变化。在研究期间CRP没有变化。
这些结果表明，急性缺氧导致IL-6水平短暂升高，并对OSA尤其是儿童期心血管疾病增加的发病机制有影响。
