Integrated Metabolomics Analysis of Kidney

As previously mentioned, the integrated metabolomics analysis in this study was conducted by GC–MS and UPLC–MS. The methodology has previously been described (Cao et al., 2020 (link)). In brief, GC–MS analysis was conducted using an Agilent 7890B gas chromatography system coupled to an Agilent 5977A MSD system (Agilent Technologies Inc., CA, United States). UPLC–MS analysis was performed using a Dionex Ultimate 3,000 RS UHPLC system fitted with Q-Exactive quadrupole-Orbitrap mass spectrometer equipped with a heated electron spray ionization (ESI) source (Thermo Fisher Scientific, Waltham, MA, United States) to analyze metabolic profiling in both positive and negative ion modes. The detailed sample preparation, workflow of GC–MS, and UPLC–MS analysis of kidney homogenates are described in the Supplemental methods.