Screening Of Biomarkers Of Ischemic Stroke Based On Mass Spectrometry

Objective:Mass spectrometry was used to screen proteomic and metabonomic markers reflecting the characteristics of ischemic stroke.Methods:1.After 14 kinds of high abundance proteins(Albumin,Ig A,Ig D,Ig G,Ig E,Ig M,α 1-acid glycoprotein,α 1-antitrypsin,α 2-macroglobulin,apolipoprotein A1,fibrinogen,haptoglobin,transferrin)were removed from the blood of patients with ischemic stroke by microcentrifugation column,the serum without high abundance proteins was quantitatively detected by liquid chromatography and tandem mass spectrometry.2.The detected proteins were screened for potential proteome markers of ischemic stroke,and their biological functions were analyzed by protein interaction network analysis,gene ontology analysis and Kyoto gene and genome encyclopedia.After the analysis of the PPI network,MPO,CRP,LCN2,MMP9,S100A9,and CTSG were identified as key proteins.Except the S100A9,the expression level of other proteins was consistent with that of m RNA.3.Through the analysis of the samples,a total of 1442 metabolites were detected in positive ion mode,and 22 differential metabolites were determined.A total of 1239 metabolites were detected in negative ion mode,and 32 differential metabolites were determined.4.KEGG pathway analysis suggests that primary bile acid synthesis,valine,leucine and isoleucine metabolism,caffeine metabolism,phenylalanine metabolism,and terpene main chain biological ischemic stroke are closely related.Results: 1.The samples with high abundance were detected and analyzed by liquid chromatography and tandem mass spectrometry,and a total of 1569 proteins were identified.2.Through the screening of the identified proteins,a total of 61 differential proteins were obtained,including 52 up-regulated proteins and 9 down-regulated proteins.There are 439 enrichment pathways in GO function analysis.CC biological process mainly includes secretory granule lumen,cytoplasmic vesicle,platelet Alpha granule and so on;BP biological process mainly includes humoral immunity,antibacterial activity,blood coagulation and so on;MF process mainly includes lowdensity lipoprotein binding,antioxidant activity,lipoprotein particle binding and so on.3.Through the analysis of the samples,a total of 1442 metabolites were detected in positive ion mode,and 22 differential metabolites were determined.A total of 1239 metabolites were detected in negative ion mode,and 32 differential metabolites were determined.4.KEGG pathway analysis showed that primary bile acid synthesis,aminoacyl t RNA biosynthesis,valine,leucine and isoleucine metabolism,caffeine metabolism and phenylalanine metabolism were closely related to ischemic stroke.Conclusion: The potential markers were screened for ischemic stroke,such as MPO,CRP,LCN2,MMP9,S100A9,CTSG and L-Isoleucine,α-Hydroxyhippuric acid.