Abstract
INTRODUCTION: Chemotherapy-induced thrombocytopenia (CIT) presents as a prevalent hematological toxicity, often complicating the clinical management of cancer patients. SI XIAN Formula (SXF), a prescription consisting of ten traditional Chinese medicine for treating chemotherapy-induced thrombocytopenia (CIT), has been widely used to treat CIT patients more than 10 years. The mechanism of SXF remains unclear. This study was designed to systematically evaluate the therapeutic efficacy and elucidate the underlying mechanisms of SXF in a CIT mouse model. METHODS: A CIT mice model was successfully established via the tail vein injection of carboplatin. The Mice were subsequently treated daily with SXF for 15 days and 24 days. Body weight and platelet count were recorded every 3 days. The bone marrow cells and fluid were collected for flow cytometry analysis and cytokine detection separately. Histological changes in the femurs bone marrow were observed using H&E staining. The diversity and composition of the intestinal microbiota were analyzed using 16S rDNA gene sequencing. The bone marrow metabolites were identified by HPLC-MS/MS analysis. RESULTS: SXF administration significantly accelerated the recovery of platelet counts to baseline levels following carboplatin -induced thrombocytopenia. Mechanistically, SXF demonstrated protective effects on multiple hematopoietic cells, including hematopoietic stem/progenitor cells, megakaryocytic progenitor cells, and bone marrow megakaryocytes in CIT-induced mice. Furthermore, SXF effectively restored carboplatin-induced alterations in hematopoietic cytokine profiles. SXF treatment altered gut microbial diversity and community structure, particularly reducing the abundance of Paraprevotella and Bacteroides while increasing the abundance of Lachnospiraceae_NK4A136 compared with the model group, which is positively correlated with all hematopoietic function indicators (P < 0.001). Metabolomic profiling further revealed that SXF ameliorated the bone marrow metabolic profile in CIT-induced mice. Spearman correlation analysis revealed significant positive associations between Parabacteroides, Prevotellaceae_UCG-001, Bacillus, and unclassified Muribaculaceae with upregulated metabolites, while showing inverse correlations with downregulated metabolites in SXF(H) versus MDL group comparisons. Our findings demonstrate that SXF alleviates CIT in mice by orchestrating a novel gut-bone marrow regulatory axis, bridging gut microbiota and marrow metabolic remodeling. CONCLUSION: In CIT murine models, SXF administration was shown to alleviate carboplatin-induced bone marrow microenvironment injury and accelerate platelet recovery via bidirectional regulation of gut microbiota and marrow metabolic remodeling.