Vascular inflammation in obesity and sleep apnea.
Vascular inflammation in obesity and sleep apnea.
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DOI:
10.1161/circulationaha.109.900357
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发表时间:
2010-03-02
期刊:
影响因子:
37.8
通讯作者:
Le Jemtel TH
中科院分区:
文献类型:
--
作者:
Jelic S;Lederer DJ;Adams T;Padeletti M;Colombo PC;Factor PH;Le Jemtel TH
Unrecognized obstructive sleep apnea (OSA) is highly prevalent in obesity. Both obesity and OSA are associated with vascular endothelial inflammation and increased risk for cardiovascular diseases. We investigated directly whether endothelial alterations that are commonly attributed to obesity are in fact related to OSA. Seventy-one subjects with body mass index (BMI) ranging from normal to obese underwent attended polysomnography. To assess directly vascular inflammation and oxidative stress, we quantified expression of nuclear factor kappa B (NFκB) and nitrotyrosine by immunofluorescence in freshly harvested venous endothelial cells. To evaluate basal endothelial nitric oxide (NO) production and activity, we quantified expression of endothelial NO synthase (eNOS) and phosphorylated eNOS (P-eNOS). Vascular reactivity was measured by brachial artery flow-mediated dilation (FMD). Expression of eNOS and P-eNOS and FMD were significantly lower whereas expression of nitrotyrosine was significantly greater in OSA patients (n=38) than in OSA-free subjects (n=33) regardless of central adiposity. Expression of NFκB was greater in obese OSA patients than in obese OSA-free subjects (p=0.004). Protein expression and FMD were not significantly affected by increasing BMI or central obesity in OSA patients and in OSA-free subjects. After 4 weeks of continuous positive airway pressure (CPAP) therapy, FMD and expression of eNOS and P-eNOS significantly increased whereas expression of nitrotyrosine and NFκB significantly decreased in OSA patients who adhered with CPAP≥4 hours daily. Untreated OSA rather than obesity is a major determinant of vascular endothelial dysfunction, inflammation and elevated oxidative stress in obese patients.