Vascular and Inflammatory High Fat Meal Responses in Young Healthy Men; A Discriminative Role of IL-8 Observed in a Randomized Trial

BackgroundHigh fat meal challenges are known to induce postprandial low-grade inflammation and endothelial dysfunction. This assumption is largely based on studies performed in older populations or in populations with a progressed disease state and an appropriate control meal is often lacking. Young healthy individuals might be more resilient to such challenges. We therefore aimed to characterize the vascular and inflammatory response after a high fat meal in young healthy individuals.
MethodsIn a double-blind randomized cross-over intervention study, we used a comprehensive phenotyping approach to determine the vascular and inflammatory response after consumption of a high fat shake and after an average breakfast shake in 20 young healthy subjects. Both interventions were performed three times.
ResultsMany features of the vascular postprandial response, such as FMD, arterial stiffness and micro-vascular skin blood flow were not different between shakes. High fat/high energy shake consumption was associated with a more pronounced increase in blood pressure, heart rate, plasma concentrations of IL-8 and PBMCs gene expression of IL-8 and CD54 (ICAM-1), whereas plasma concentrations of sVCAM1 were decreased compared to an average breakfast.
ConclusionWhereas no difference in postprandial response were observed on classical markers of endothelial function, we did observe differences between consumption of a HF/HE and an average breakfast meal on blood pressure and IL-8 in young healthy volunteers. IL-8 might play an important role in dealing with high fat challenges and might be an early marker for endothelial stress, a stage preceding endothelial dysfunction.
Trial RegistrationClinicalTrials.gov NCT00766623

背景
已知高脂饮食负荷可诱发餐后低度炎症与内皮功能障碍。此类认知大多基于老年人群或已进展为疾病状态人群的相关研究，且往往缺乏合适的对照餐食。年轻健康个体或许对这类负荷具有更强的耐受性。为此，本研究旨在明确年轻健康个体摄入高脂餐食后的血管与炎症反应特征。

方法
本研究采用双盲随机交叉干预设计，纳入20名年轻健康受试者，通过全面表型分析手段，分别检测受试者摄入高脂奶昔与普通早餐奶昔后的血管及炎症反应。两种干预措施均重复开展3次。

结果
两种奶昔干预后，餐后血管反应的多项指标，如血流介导的血管舒张（Flow-mediated Dilation, FMD）、动脉僵硬度及皮肤微血管血流量均无显著差异。与普通早餐奶昔相比，摄入高脂/高能量奶昔后，受试者的血压、心率、血浆白细胞介素8（Interleukin-8, IL-8）浓度以及外周血单个核细胞（Peripheral Blood Mononuclear Cells, PBMCs）中IL-8与CD54（细胞间黏附分子1, Intercellular Adhesion Molecule 1, ICAM-1）的基因表达均出现更显著的升高，而血浆可溶性血管细胞黏附分子1（soluble Vascular Cell Adhesion Molecule 1, sVCAM1）浓度则有所降低。

结论
尽管在经典内皮功能标志物的餐后反应方面未观察到显著差异，但本研究在年轻健康志愿者中发现，摄入高脂高能量（High Fat/High Energy, HF/HE）餐食与普通早餐餐食相比，其血压与IL-8水平存在显著差异。IL-8或许在应对高脂负荷过程中发挥重要作用，且可能作为内皮应激（内皮功能障碍前期阶段）的早期标志物。

试验注册
ClinicalTrials.gov NCT00766623