Preliminary Study On Metabolomics And Proteomics In Neuropsychiatric Systemic Lupus Erythematosus

Part 1 Metabolomics study of NPSLEObjective:(1)To analyze the metabolic characteristics of serum samples from SLE patients with NPSLE by liquid chromatography with mass spectrometry(LC-MS),and exploring the potential markers for the diagnosis of NPSLE.(2)To identify biologically meaningful patterns and performed pathway analysis through the metabolomics data.Methods: 60 SLE patients who were distributed to the experiment group in the First Affiliated Hospital of Guangxi Medical University from June 2018 to June 2020 were prospectively enrolled in our study.10 people mathed with age,without Infections,tumors,metabolic disorders and other immune diseases who were used as the control group.And their serum samples were collected for discovery profile.Fruther,the experiment group was categoried into SLE patients with neuropsychiatric(NPSLE,n=20)and SLE patients without neuropsychiatric(non-NPSLE,n=40).The LC-MS based non-targeted metabolomics approach was used to identify the differential metabolites between each groups.And the metabolites data were analyzed by HMDB(Human Metabolome Database)and KEGG(Kyoto Encyclopedia of Genes and Genomes)to identify the metabolite structure and explore the main pathways.Results:(1)The age of onset of 20 NPSLE patients was in aged 12.14±2.21 years old.All of NPSLE patients were presented central nervous system symptoms,including headache(n=11,55%),seizures(n=9,45%),cerebrovascular accident(n=3,15%),demyelinating syndrome(n=6,30%)and mental disorder(n=3,15%).Compared with non-NPSLE group,NPSLE group had higher SLEDAI,lower levels in Complement(C3 and C4),lower platelets count and positive anti-cardiolipin antibody(P<0.05).(2)The difference of serum metabolism in the SLE patients and controls was significant,identifying 36 metabolites(positive ion mode)and 38 metabo-lites(negative ion mode).The difference in NPSLE and non-NPSLE groups was lithe,identifying 15 metabolites(positive ion mode)and 16 metabolites(nega-tive ion mode).The above metabolites involved fatty acids,amino acids,carboxylic acids,sterols and lipids,and so on.(3)These differential metabolites of NPSLE mainly involved in D-Glutamine and D-glutamate metabolism,arginine biosynthesis,arginine and proline metabolism,aminoacyl-t RNA biosynthesis,nitrogen metabolism,and synthesis and degradation of ketone bodies.(4)The metabolites of SLE group vs CON and NPSLE vs non-NPSLE group were identified 12 differential metabolites,such as L-glutamic acid,3-anisic acid and L-lactic Acid.The AUC of 12 metabolites were greater than 0.5 and that could assist in the identification of NPSLE and non-NPSLE group.Conclusion:(1)Compared with non-NPSLE group,NPSLE patients characterised by higher SLEDAI,lower levels in complement(C3 and C4),lower platelets count and positive anti-cardiolipin antibody.(2)74 different sinifigant metabolites(such as phytosphingosine)were identified in SLE/CON comparsion,34 different sinifigant metabolites(such as D-pyroglutamic acid)were identified in NPSLE/non-NPSLE comparsion.(3)NPSLE-related differential metabolites mainly involved D-glutamine and D-glutamate metabolism,arginine biosynthesis and arginine and proline metabolism.(4)12 metabolites,such as L-glutamic acid may be potencial marker of NPSLE.Part Ⅱ Proteomics study of NPSLEObjective: To evaluate the serum biomarker from SLE patients vs controls and NPSLE vs non-NPSLE groups by quantitative proteomic analysis,and explore the canonical pathways and mechanisms involved by bioinformatics analysis,including KEGG and PPI network.Methods: 9 SLE patients and 2 controls who were respectively distributed to the experiment group and control group in the First Affiliated Hospital of Guangxi Medical University from June 2018 to June 2020 were prospectively enrolled in our study.And NPSLE group(n=3)and non-NPSLE group(n=6)were classified into the experiment group,and their serum samples were collected.The TMT based on proteomic approach was used to evaluate the differential expressed proteins(DEP),and analyzed by KEGG and PPI network.Results:(1)15 DEP(such as alpha-2-HS-glycoprotein),were identified in SLE/CON comparsion,including 2 significantly upregulated(FC ≥ 1.2 and P<0.05)and 13 significantly downregulated(FC≤1/1.2 and P<0.05).(2)34 DEP(such as coagulation factor XIII A chain),were identified in NPSLE/comparsion,including 32 significantly upregulated(FC≥1.2 and P< 0.05)and 2 significantly downregulated(FC≤1/1.2 and P<0.05).(3)NPSLE-related DEP were mainly involved in multiple pathways,such as complement and coagulation cascades,platelet activation,chemokine signaling pathway,staphylococcus aureus infection,viral protein interaction with cytokine and cytokine receptor,and Rap1 signaling pathway.(4)25 DEP(such as trem-like transcript 1 protein,TREML1)were identified in the PPI network and consider to be critical biomarkers in NPSLE.Conclusion:(1)25 DEP(such as TREML1)were consider to be potential marker of NPSLE.(2)NPSLE-related DEP mainly concentrated in complement and coagulation cascades,platelet activation and chemokine signaling pathway.