Dynamic changes of serum metabolite profiling in septic mice based on high performance liquid chromatography of quadrupole time of flight mass spectrometry analysis

The objective of this study is to gain insights into the underlying metabolic transformations that occurred during the whole progression of cecal ligation and puncture (CLP)-induced sepsis, thus providing new targets for its treatment. High-performance liquid chromatography of quadrupole time of flight mass spectrometry (HPLC-Q-TOF-MS/MS) combined with multivariate statistical techniques was used to detect the s in serum from septic mice. Fifty male mice were divided into two groups, including the sham group (n = 7) and the CLP-induced sepsis group (n = 43). Animals were sacrificed at 1, 3, 5, and 7 days post-CLP and then serum were collected for metabolomic analysis. Multivariate regression analysis was carried out through MetaboAnalyst 5.0, including principal component analysis (PCA) and partial least squares discriminant analysis (PLS-DA), to identify the s and screen out the related differential metabolites. Besides, the KEGG pathway analysis was used to analyze the related metabolic pathways in which the identified metabolites were involved. Based on the fold change (FC > 2.0 or <0.5), variable important in projection (VIP > 1.2), and P value (P < 0.05), we found 26, 17, 21, and 17 metabolites in septic mice at 1, 3, 5, and 7 days post-CLP, respectively, compared with that of the sham group. The PCA and PLS-DA pattern recognition showed a cluster-type distribution between the sham group and the CLP group. Dysregulated amino acid metabolism, as well as disturbed nucleotide metabolism, is observed. Several important metabolic pathways were identified between the sham group and the CLP group. Among them, phenylalanine metabolism, phenylalanine, tyrosine, and tryptophan biosynthesis showed striking at day 1 post-CLP. At day 3, phenylalanine, tyrosine, and tryptophan biosynthesis changed significantly. However, as the disease process, only pyrimidine metabolism showed the most significant alternation, compared to the sham group. Several differential metabolites were identified in the CLP group compared with that of the sham group and they were presented with dynamic alternation at different time points post-CLP, indicating metabolic disturbance occurred throughout the whole sepsis progression.