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Hplc-Ms/Ms Analysis of Key Components of the Amino Acid Metabolism in the Serum of Acute Myocardial Infarction Patients

Objective: The present study aimed to identify the key components of amino acids and potential mechanistic pathways of myocardial infarction. 
 
Methods: We performed case–control metabolite profiling via mass spectrometry in the serum obtained from 33 individuals with acute myocardial infarction, and compared the results to matched healthy volunteers (70 cases). Multi-reaction monitoring was used to evaluate the targeted metabolomics of amino acids by high performance liquid chromatography and tandem mass spectrometry; this method was validated using the standard solution. Moreover, we used the mixed effects models to compare the metabolite concentrations between the cases and controls by regulating relevant biological variables. 
 
Results: LC-MS/MS quantitatively determined 33 substances in amino acid metabolism and intestinal microbial metabolites, and provided good results in terms of accuracy, precision, and linearity. The method was validated according to Food and Drug Administration guidelines, and it provided good results in terms of precision, accuracy, and linearity. Thus, significant changes were observed in the aromatic amino acids (tyrosine, phenylalanine, and tryptophan), oxidative homeostasis (o-tyrosine), intestinal microbial metabolites (trimethylamine oxide, choline, acetylcholine), and methionine cycle (SAM, SAH, methionine, and homocysteine). 
 
Conclusions: A unique metabolite profile involving amino acid and intestinal microbial metabolites is observed in myocardial infarction disorders. The endogenous compounds evaluated in this study can be used as potential biomarkers. 
 
Funding Information: This work was supported by the National Natural Science Foundation of China (No. 81803689), the Natural Science Foundation of Guangdong Province (No. 2018A030310292), Project of Health Science and Technology of Guangzhou (No. 20191A011039), and the YIWEN Talent Project of The Third Affiliated Hospital of Guangzhou Medical University (No. 2021#9). 
 
Declaration of Interests: The authors declare no competing financial interest. 
 
Ethics Approval Statement: The study was approved by the Medical Ethics Committee of the Third Clinical School of Guangzhou Medical University. Acute myocardial infarction human serum samples and healthy human serum samples were obtained from The Third Clinical School of Guangzhou Medical University, and informed consent was obtained from all patients (batch numbers of ethical approval: 2021#026).