Service of Genetics, Department of Pediatrics, Faculty of Medicine and Health Sciences, Université de Sherbrooke, 3001 12th Avenue North, Sherbrooke (Québec), Canada J1H 5N4.
Anal Chem. 2013 Feb 5;85(3):1743-52. doi: 10.1021/ac303033v. Epub 2013 Jan 7.
Fabry disease is a lysosomal storage disorder caused by the absence or reduction of α-galactosidase A enzyme activity. The enzymatic deficiency results in the impaired catabolism of neutral sphingolipids with terminal α-galactosyl residues and subsequent accumulation in several tissues. Biomarkers reflecting disease severity and progression, the response to therapeutic intervention, and details of molecular pathogenesis are needed. Until now, two sphingolipids were targeted as biomarkers in urine and plasma of Fabry patients: globotriaosylceramide (Gb(3)) and globotriaosylsphingosine (lyso-Gb(3)). Using metabolomic approaches, our group recently discovered seven novel urinary lyso-Gb(3)-related Fabry disease biomarkers with mass-to-charge ratios (m/z) of 758, 774, 784, 800, 802, 820, and 836. All these biomarkers exhibited modifications of the lyso-Gb(3) sphingosine moiety. The aims of the present study were to devise and validate a specific tandem mass spectrometry multiplex methodology for the relative quantification of these seven analogues and to evaluate their urinary excretion levels in samples from 164 Fabry patients and 94 healthy controls. We found no detectable analogues in healthy controls, except for trace amounts of the analogue with m/z 836. Significant correlations were established between lyso-Gb(3) analogue levels in urine and gender (p < 0.001). Fabry males had higher excretion levels compared to females with the disease. Lyso-Gb(3) analogue levels correlated well with enzyme replacement therapy (ERT) status in males (p < 0.05). The urinary analogue distributions varied among Fabry patients. However, the analogues with m/z 802, 820, and 836 were generally more abundant in the majority of patients. Lyso-Gb(3) analogues are promising urinary biomarkers for Fabry disease.
法布里病是一种溶酶体贮积病，由α-半乳糖苷酶 A 酶活性缺失或减少引起。酶的缺乏导致带有末端α-半乳糖基残基的中性鞘脂的代谢分解受损，随后在几种组织中积累。需要反映疾病严重程度和进展、治疗干预反应以及分子发病机制细节的生物标志物。到目前为止，两种鞘脂已被作为法布里病患者尿液和血浆中的生物标志物：神经酰胺三己糖苷（Gb(3)）和神经酰胺三己糖苷（lyso-Gb(3)）。我们的研究小组最近使用代谢组学方法发现了七种新型尿 lyso-Gb(3)相关法布里病生物标志物，其质荷比（m/z）分别为 758、774、784、800、802、820 和 836。所有这些生物标志物均显示 lyso-Gb(3)神经酰胺部分的修饰。本研究的目的是设计和验证一种用于相对定量分析这七种类似物的特定串联质谱多重方法，并评估其在 164 名法布里病患者和 94 名健康对照者尿液中的排泄水平。我们在健康对照者中未检测到可检测的类似物，除了 m/z 836 的类似物有微量存在。在尿 lyso-Gb(3)类似物水平与性别之间建立了显著相关性（p <0.001）。法布里男性患者的排泄水平高于女性患者。尿 lyso-Gb(3)类似物水平与男性患者的酶替代治疗（ERT）状态相关（p <0.05）。法布里病患者的尿类似物分布不同。然而，m/z 802、820 和 836 的类似物在大多数患者中通常更为丰富。lyso-Gb(3)类似物是法布里病有前途的尿生物标志物。
