Metabolomic analysis of amino acids and organic acids in aging mouse eyes using gas chromatography–tandem mass spectrometry

This is a metabolomics study for monitoring altered amino acid (AA) and organic acid (OA) metabolism of in eyes from aging an mouse model at 8 and 18 weeks and 18 months. Simultaneous metabolic profiling analysis of OAs and AAs was performed as ethoxycarbonyl/methoxime/tert‐butyldimethylsilyl derivatives by gas chromatography–tandem mass spectrometry. A total of 42 metabolites—24 AAs and 18 OAs—were determined and their composition values were normalized to the corresponding mean values of 8‐week‐old mice as the control group. Then their normalized values were plotted as star graphs, which were distorted and readily distinguishable for each age‐related group. Among the 42 metabolites, 18 AAs and 11 OAs were age dependent and significantly different (p