Preliminary Studies On Peptidomics And Metabonomics Of Cerebral Infarction With Blood Stasis Syndrome

The aim of peptidomics and metabonomics is to perform the quantification and identification of peptides and metabolites within an organism, tissue, or even a cell. They are important for disease diagnosis and pathogenesis research. Cerebral infarction, which is called "apoplexy" in traditional Chinese medicine (TCM), is a frequently-occurring disease in older age groups. Blood stasis syndrome is one of basic syndromes of this disease. In this work, we carried out preliminary studies on the plasma peptidomics and metabonomics of cerebral infarction with blood stasis syndrome to get the characteric biological markers'profiles of symptomatology, thus establishing molecular testing technologies of TCM differentiation. This work will provide evidence to disease diagnosis, prognostic monitoring and pathogenesis research. The main contents of this paper are described as follows:1. Plasma sample preparation method for peptidomics researchIn this section, peptides extraction effiencies of centrifugal ultrafiltration and solid phase extraction were compared. The addition of acetonitrile and formic acid as denaturants before ultrafiltration was optimized. Different desalting and enrichment methods after ultrafiltration were studied. The results showed that centrifugal ultrafiltration could extract more peptides.The addition of 80%acetonitrile and 0.1% formic acid before ultrafiltration could improve the extraction effiency. And desalting after uluafiltration would lead to serious loss of peptides.2. Analysis of eight peptides by high performance liquid chromatography coupled with mass spectrometry (LC-MS)In this section, a LC-MS method for the determination of eight endogenous peptides, including angiotensin-Ⅱ, neurotensin,5-met-enkephalin,5-leu-enkephalin, somatosiatin, bradykinin, dynorphin A and oxidized glutathione, was developed. These peptides were reported to have relates with cerebral infarction. The developed method will contribute to the analysis of these peptides in biological samples.3. Study on data processing methods for peptidomics researchIn this section, auto integration by XCMS and manual integration were applied in processing peptidomics data. The results showed that the peaks areas and t-test results obtained from the two data processingn methods were quite different. And manual integmtion combined with picking out ion peaks by XCMS was a better method.4. P(?)liminary studies on peptidomics and metabonomics of cerebral infarction with biood stasis syndromeIn this section, plasma samples of 41 healthy subjects,46 patients of cerebral infarction with blood stasis syndrome before and after therapy were analyzed by LC-MS for peptidomics study. In addition, these samples were analyzed by gas chromatography coupled with mass spectrometry (GC-MS) after derivatization for metabonomics study. The data was processed by genetic algorithm and 18 potiential biomarkers were selected. These potiential biomarkers would provide evidence to diagnosis and prognostic monitoring of cerebral infarction with blood stasis syndrome.