Metabolic Profiling of Systemic Lupus Erythematosus and Comparison with Primary Sjögren's Syndrome and Systemic Sclerosis

• Published in: PloS one Vol. 11; no. 7; p. e0159384
• Main Authors: Bengtsson, Anders A, Trygg, Johan, Wuttge, Dirk M, Sturfelt, Gunnar, Theander, Elke, Donten, Magdalena, Moritz, Thomas, Sennbro, Carl-Johan, Torell, Frida, Lood, Christian, Surowiec, Izabella, Rännar, Stefan, Lundstedt, Torbjörn
• Format: Journal Article
• Language: English
• Published: United States Public Library of Science 01.07.2016; Public Library of Science (PLoS)
• Subjects: Adult; Amino acids; Autoimmune diseases; Bioinformatics and Systems Biology; Bioinformatik och systembiologi; Biology and Life Sciences; Biomarkers; Case-Control Studies; Chronic conditions; Clinical Medicine; Complement system; Demography; Discriminant Analysis; Disease; Drug metabolism; Enzymes; Female; Humans; Immunology; Inflammation; Joint diseases; Kidneys; Klinisk medicin; Least-Squares Analysis; Life sciences; Lupus; Lupus Erythematosus, Systemic - metabolism; Male; Medical and Health Sciences; Medicin och hälsovetenskap; Medicine and Health Sciences; Metabolism; Metabolites; Metabolomics; Metabolomics - methods; Middle Aged; Mortality; Oxidative stress; Pathogenesis; Phenotype; Principal Component Analysis; Reumatologi och inflammation; Rheumatic diseases; Rheumatology; Rheumatology and Autoimmunity; Scleroderma; Scleroderma, Systemic - metabolism; Sensitivity and Specificity; Sjogren's syndrome; Sjogren's Syndrome - metabolism; Systemic lupus erythematosus; Systemic sclerosis; Tryptophan; Urea; Xanthine oxidase; Young Adult
• ISSN: 1932-6203; 1932-6203
• DOI: 10.1371/journal.pone.0159384

Systemic lupus erythematosus (SLE) is a chronic inflammatory autoimmune disease which can affect most organ systems including skin, joints and the kidney. Clinically, SLE is a heterogeneous disease and shares features of several other rheumatic diseases, in particular primary Sjögrens syndrome (pSS) and systemic sclerosis (SSc), why it is difficult to diagnose The pathogenesis of SLE is not completely understood, partly due to the heterogeneity of the disease. This study demonstrates that metabolomics can be used as a tool for improved diagnosis of SLE compared to other similar autoimmune diseases. We observed differences in metabolic profiles with a classification specificity above 67% in the comparison of SLE with pSS, SSc and a matched group of healthy individuals. Selected metabolites were also significantly different between studied diseases. Biochemical pathway analysis was conducted to gain understanding of underlying pathways involved in the SLE pathogenesis. We found an increased oxidative activity in SLE, supported by increased xanthine oxidase activity and an increased turnover in the urea cycle. The most discriminatory metabolite observed was tryptophan, with decreased levels in SLE patients compared to control groups. Changes of tryptophan levels were related to changes in the activity of the aromatic amino acid decarboxylase (AADC) and/or to activation of the kynurenine pathway.