Ultraperformance liquid chromatography-mass spectrometry based comprehensive metabolomics combined with pattern recognition and network analysis methods for characterization of metabolites and metabolic pathways from biological data sets.

Metabolomics is the study of metabolic changes in biological systems and provides the small molecule fingerprints related to the disease. Extracting biomedical information from large metabolomics data sets by multivariate data analysis is of considerable complexity. Therefore, more efficient and optimizing metabolomics data processing technologies are needed to improve mass spectrometry applications in biomarker discovery. Here, we report the findings of urine metabolomic investigation of hepatitis C virus (HCV) patients by high-throughput ultraperformance liquid chromatography-mass spectrometry (UPLC-MS) coupled with pattern recognition methods (principal component analysis, partial least-squares, and OPLS-DA) and network pharmacology. A total of 20 urinary differential metabolites (13 upregulated and 7 downregulated) were identified and contributed to HCV progress, involve several key metabolic pathways such as taurine and hypotaurine metabolism, glycine, serine and threonine metabolism, histidine metabolism, arginine and proline metabolism, and so forth. Metabolites identified through metabolic profiling may facilitate the development of more accurate marker algorithms to better monitor disease progression. Network analysis validated close contact between these metabolites and implied the importance of the metabolic pathways. Mapping altered metabolites to KEGG pathways identified alterations in a variety of biological processes mediated through complex networks. These findings may be promising to yield a valuable and noninvasive tool that insights into the pathophysiology of HCV and to advance the early diagnosis and monitor the progression of disease. Overall, this investigation illustrates the power of the UPLC-MS platform combined with the pattern recognition and network analysis methods that can engender new insights into HCV pathobiology.

[The expression of calcium-sensing receptor in rats with acute myocardial infarction and its effect on cells apoptosis].

OBJECTIVE: To investigate the change of calcium sensing receptor (CaSR) expression at different time in rat tissue with acute myocardial infarction (AMI) and its effect on cardiomyocyte apoptosis. METHODS: The healthy Wistar rats were randomly divided into Sham and AMI groups, the rat myocardial infarction model was established by ligating left anterior descending coronary artery. The changes of cardiac morphology and hemodynamics were detected at 1, 2 and 4 weeks,respectively. The expressions of CaSR mRNA and protein in myocardial tissue were detected by RT-PCR and Western blot, respectively. The expressions of Bax, Bcl-2, caspase-3 and caspase-9 proteins were detected by Western blot. The serum levels of lactate dehydrogenase (LDH), creatine kinase (CK) activity and cardiac troponin (cTnT) were determined. The apoptosis of cardiomyocytes were tested by TUNEL staining. RESULTS: Compared with the sham group, the expressions of CaSR mRNA and protein, the apoptosis index were increased significantly with the development of AMI (P＜0.05). The ultrastructural damage of cardiomyocytes was serious; the levels of LVSP, +dp/dtmax and -dp/dtmax were decreased,while the levels of LVEDP was increased (P＜0.05); In AMI group, the cTnT level, CK and LDH activities were all increased (P＜0.05). With the development of myocardial infarction, the cTnT level and CK activity were gradually decreased, while the activity of LDH was not significantly changed. The expressions of promote apoptosis-related Bax, caspase-3 and caspase-9 were significantly increased, and the expression of inhibited apoptosis-related protein(factor)Bcl-2 was significantly decreased (P＜0.05). CONCLUSION: With the development of myocardial infarction,the expressions of CaSR mRNA and protein,the apoptosis index in rat myocardial tissue were increased with time prolongation after AMI. The increased expression of CaSR is involved in rat myocardial infarction, which is related with apoptosis.