Department of Surgical and Gastroenterological Sciences, University of Padova, Padova, Italy.
Clin Chem Lab Med. 2011 Feb;49(2):197-206. doi: 10.1515/CCLM.2011.055. Epub 2010 Dec 14.
Hepcidin has emerged as the primary regulator of iron homeostasis. Previous studies on assessing urinary hepcidin are limited. We developed a method for quantifying hepcidin-25 (Hep-25) in plasma using surface-enhanced laser-desorption-ionization time-of-flight mass spectrometry (SELDI-TOF/MS) and a 25-AA peptide as reference standard. The aims of the study were 1) to assess the performance of this method in different conditions of iron metabolism disorders; 2) to assess the diagnostic validity of non-invasive serum biomarkers in the identification of iron overload.
Validation of the method was performed in 10 patients with type I hemochromatosis (HE) and in 177 subjects previously enrolled in a general population epidemiological study. Among the latter group, 17 had non-alcoholic fatty liver disease, 10 had chronic hepatitis C, and 150 subjects had normal ultrasound, normal liver function tests (LFTs), an alcohol intake < 20 g ethanol/day and were negative for the C282Y mutation. The following biomarkers were assayed in each case: plasma Hep-25, C282Y and H63D mutations of the HFE gene; serum iron, ferritin (SF), transferrin saturation, transaminases, γ-glutamyltransferase (GGT), glucose, insulin, total cholesterol, high-density lipoprotein (HDL)-cholesterol, low-density lipoprotein (LDL)-cholesterol and triglycerides.
Plasma Hep-25 concentrations were higher in HCV+ patients (26.3 ± 7.2 nmol/L) than in controls, and correlated positively with SF (p < 0.001). H63D heterozygous subjects revealed a pattern of iron overload that was significantly higher than H63D wild type subjects. Analyzing the data with the Biomarker Pattern 5.0.2. software to identify the most significant biomarkers for discriminating between HE cases and controls allowed us to produce an algorithm with four terminal nodes, which included glucose > 4.8 mmol/L and Hep-25/SF ratio ≤ 6.6 as the main splitters. These variables enabled the correct diagnosis of HE with 100% sensitivity, 93% specificity and an area under the receiver operating characteristic (ROC) curve of 0.993.
Our plasma Hep-25 mass spectrometry method yields measurements that reflect pathological and genetic influences; simple non-invasive biomarkers (Hep-25/SF ratio and glucose) can predict the presence of HE.
铁调素已成为铁稳态的主要调节剂。以前对尿铁调素的评估研究有限。我们开发了一种使用表面增强激光解吸电离飞行时间质谱（SELDI-TOF/MS）和 25-AA 肽作为参考标准定量检测血浆中铁调素-25（Hep-25）的方法。该研究的目的是 1）评估该方法在不同铁代谢紊乱条件下的性能；2）评估非侵入性血清生物标志物在识别铁过载中的诊断有效性。
在 10 例 1 型血色病（HE）患者和之前参加一般人群流行病学研究的 177 名受试者中对该方法进行了验证。在后一组中，17 例患有非酒精性脂肪性肝病，10 例患有慢性丙型肝炎，150 例受试者超声正常，肝功能检查（LFT）正常，饮酒<20 g 乙醇/天，且 C282Y 突变阴性。在每种情况下均测定以下生物标志物：血浆 Hep-25、HFE 基因的 C282Y 和 H63D 突变；血清铁、铁蛋白（SF）、转铁蛋白饱和度、转氨酶、γ-谷氨酰转移酶（GGT）、葡萄糖、胰岛素、总胆固醇、高密度脂蛋白（HDL）-胆固醇、低密度脂蛋白（LDL）-胆固醇和甘油三酯。
HCV+患者的血浆 Hep-25 浓度（26.3±7.2 nmol/L）高于对照组，且与 SF 呈正相关（p<0.001）。H63D 杂合子患者表现出的铁过载模式明显高于 H63D 野生型患者。使用 Biomarker Pattern 5.0.2 软件分析数据以识别区分 HE 病例和对照组的最显著生物标志物，允许我们生成一个具有四个终端节点的算法，其中包括葡萄糖>4.8 mmol/L 和 Hep-25/SF 比值≤6.6 作为主要分裂器。这些变量使 HE 的正确诊断具有 100%的灵敏度、93%的特异性和 0.993 的接收器工作特征（ROC）曲线下面积。
我们的血浆 Hep-25 质谱方法得出的测量结果反映了病理和遗传影响；简单的非侵入性生物标志物（Hep-25/SF 比值和葡萄糖）可以预测 HE 的存在。
