Supplementary Material for: Eicosanoids and oxylipin signature in HH patients are similar to DIOS patients but are impacted by dietary iron absorption.

Introduction: Oxylipins are mediators of oxidative stress. To characterize the underlying inflammatory processes and phenotype the effect of iron metabolism disorders, we investigated the oxylipin profile in hereditary hemochromatosis (HH) and dysmetabolic iron overload syndrome (DIOS) patients.
Methods: LC-MS/MS based method to quantify plasma oxylipins in 20 HH and 20 DIOS patients in fasting conditions and 3 hours after an iron-rich meal in HH patients.
Results: Principal component analysis showed no separation between HH and DIOS, suggesting that the clinical phenotype has no direct impact on oxylipin metabolism. 20-HETE was higher in DIOS and correlated with hypertension (p = 0.03). Different oxylipin signatures were observed in HH before and after the iron-rich meal. Discriminant oxylipins include epoxy fatty acids derived from docosahexaenoic acid and arachidonic acid as well as 13-HODE and 9-HODE. Mediation analysis found no major contribution of dietary iron absorption for 16/22 oxylipins significantly affected by the meal.
Discussion: The oxylipin profiles of HH and DIOS seemed similar except for 20-HETE, possibly reflecting different hypertension prevalence between the two groups. Oxylipins were significantly affected by the iron-rich meal but the specific contribution of iron was not clear. Although iron may contribute to oxidative stress and inflammation in HH and DIOS, this does not seem to directly affect oxylipin metabolism.

引言：氧脂类是氧化应激的介质。为了表征潜在的炎症过程以及铁代谢紊乱的表型效应，我们研究了遗传性血色素沉着症（HH）和代谢性铁负荷综合征（DIOS）患者中的氧脂类谱。研究方法：采用液相色谱-串联质谱法（LC-MS/MS）对20例HH和20例DIOS患者在禁食状态下以及HH患者在富含铁的餐后3小时内的血浆氧脂类进行定量。研究结果：主成分分析显示HH和DIOS之间无显著分离，表明临床表型对氧脂类代谢无直接影响。20-HETE在DIOS中较高，并与高血压相关（p = 0.03）。在HH患者中，富含铁的餐前后观察到不同的氧脂类特征。判别性氧脂类包括源自二十二碳六烯酸和花生四烯酸的环氧脂肪酸以及13-HODE和9-HODE。中介分析发现，膳食铁吸收对16/22种受餐后显著影响的氧脂类没有产生主要贡献。讨论：HH和DIOS的氧脂类谱似无显著差异，除了20-HETE，可能反映了两组之间高血压发病率的差异。氧脂类受富含铁的餐显著影响，但铁的具体贡献尚不明确。尽管铁可能对HH和DIOS中的氧化应激和炎症有贡献，但这似乎并不直接影响氧脂类代谢。