Department of Applied Chemistry, National Chiao Tung University, Hsinchu, Taiwan;
Genomics Research Center, Academia Sinica, Taipei, Taiwan;
Clin Chem. 2016 Aug;62(8):1120-8. doi: 10.1373/clinchem.2016.256396. Epub 2016 Jun 20.
Psoriasis is a chronic, immune-mediated inflammatory skin disease. Screening skin metabolites could unravel the pathophysiology of psoriasis and provide new diagnostic approaches. Due to the lack of suitable methodologies for collecting scarce amounts of skin excretions, the psoriatic skin metabolome has not been extensively studied.
We implemented biocompatible hydrogel micropatch probes combined with mass spectrometry to investigate the skin metabolome. This noninvasive approach was applied to examine samples obtained from 100 psoriatic patients and 100 healthy individuals. We also developed custom data treatment tools and used chemometric and statistical tools to reveal the alterations in the skin metabolome caused by psoriasis.
The proposed methodology enabled us to capture alterations in the composition of skin excretions caused by the disease. Chemometric analysis revealed the major differences between the metabolomes of psoriatic skin and healthy skin. Several polar metabolites were positively (choline and glutamic acid) or negatively (urocanic acid and citrulline) correlated with the plaque severity scores. The amounts of these metabolites in the excretions sampled from psoriatic skin were significantly different (P < 0.001) from the excretions sampled from healthy skin. The role of biological variability and various confounding factors, which might affect the skin metabolome, was also investigated.
Sampling lesional and healthy skin with the hydrogel micropatch probes and subsequent direct mass spectrometry scanning provided information on the alterations in the skin metabolome caused by psoriasis, increasing the understanding of the complex pathophysiology of this disease.
银屑病是一种慢性、免疫介导的炎症性皮肤病。筛选皮肤代谢物可以揭示银屑病的病理生理学，并提供新的诊断方法。由于缺乏收集少量皮肤分泌物的合适方法，银屑病的皮肤代谢组学尚未得到广泛研究。
我们实施了生物相容性水凝胶微针探头与质谱相结合的方法来研究皮肤代谢组。这种非侵入性方法应用于检查从 100 名银屑病患者和 100 名健康个体中获得的样本。我们还开发了定制的数据处理工具，并使用化学计量学和统计工具来揭示银屑病引起的皮肤代谢组的变化。
所提出的方法使我们能够捕捉到疾病引起的皮肤分泌物组成的变化。化学计量学分析揭示了银屑病皮肤和健康皮肤代谢组之间的主要差异。几种极性代谢物与斑块严重程度评分呈正相关（胆碱和谷氨酸）或负相关（尿刊酸和瓜氨酸）。从银屑病皮肤分泌物中采样的这些代谢物的量与从健康皮肤分泌物中采样的代谢物显著不同（P < 0.001）。还研究了生物变异性和各种可能影响皮肤代谢组的混杂因素的作用。
用水凝胶微针探头采样病变和健康皮肤，然后直接进行质谱扫描，提供了银屑病引起的皮肤代谢组变化的信息，增加了对这种疾病复杂病理生理学的理解。
