Integration of organ metabolomics and proteomics in exploring the blood enriching mechanism of Danggui Buxue Decoction in hemorrhagic anemia rats

Danggui Buxue Decoction (DBD), as a classical Chinese medicine prescription, is composed of Danggui (DG) and Huangqi (HQ) at a ratio of 1:5, and it has been used clinically in treating anemia for hundreds of years. The aim of this study was to explore the treatment mechanisms of DBD in anemia rats from the perspective of thymus and spleen. In this study, a successful hemorrhagic anemia model was established, and metabolomics (UPLC-QTOF-MS/MS) and proteomics (label-free approach) together with bioinformatics (Gene Ontology analysis and Reactome pathway enrichment), correlation analysis (pearson correlation matrix) and joint pathway analysis (MetaboAnalyst) were employed to discover the underlying mechanisms of DBD. DBD had a significant blood enrichment effect on hemorrhagic anemia rats. Metabolomics and proteomics results showed that DBD regulated a total of 10 metabolites (lysophosphatidylcholines, etc.) and 41 proteins (myeloperoxidase, etc.) in thymus, and 9 metabolites (L-methionine, etc.) and 24 proteins (transferrin, etc.) in spleen. With GO analysis and Reactome pathway enrichment, DBD mainly improved anti-oxidative stress ability of thymocyte and accelerated oxidative phosphorylation to provide ATP for splenocyte. Phenotype key indexes were strongly and positively associated with most of the differential proteins and metabolites, especially nucleosides, amino acids, Fabp4, Decr1 and Ndufs3. 14 pathways in thymus and 9 pathways in spleen were obtained through joint pathway analysis, in addition, the most influential pathway in thymus was arachidonic acid metabolism, while in spleen was the biosynthesis of phenylalanine, tyrosine and tryptophan. Furthermore, DBD was validated to up-regulate Mpo, Hbb and Cp levels and down-regulate Ca2+ level in thymus, as well as up-regulate Fabp4, Ndufs3, Tf, Decr1 and ATP levels in spleen. DBD might enhance thymus function mainly by reducing excessive lipid metabolism and intracellular Ca2+ level, and promote ATP production in spleen to provide energy.