To investigate whether Fuzheng Buxue dietary therapy (FZBX) counteracts chemotherapy-induced myelosuppression (CIM) by partially modulating bone marrow mesenchymal stromal cells (MSCs) function via the Notch signaling pathway.

Ultra-high-performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS) was used to characterize the chemical constituents of FZBX. Rat MSCs were isolated by whole bone marrow adherence and were authenticated. MSCs were assigned to four groups: normal control, 5-fluorouracil (5-FU), FZBX-medicated serum, and 5-FU + FZBX-medicated serum. Cell viability was measured using the cell counting kit-8 (CCK-8) assay, and proliferation was evaluated by 5-ethynyl-2′-deoxyuridine (EdU) staining. Cell cycle distribution and apoptosis were analyzed using flow cytometry, followed by enzyme-linked immunosorbent assay (ELISA) quantification of hematopoietic cytokines. Whole transcriptome sequencing and the search tool for the retrieval of interacting genes/proteins (STRING) protein–protein interaction (PPI) network analysis were performed to explore the global transcriptional changes and interactions of Notch pathway-related genes. Western blot was used to assess the key proteins involved in the Notch pathway.

UHPLC-MS/MS identified amino acid related metabolites and herbal phytochemicals as the major constituents of FZBX. 5-FU impaired MSCs function, as evidenced by cell proliferation, induction of G0/G1 phase arrest, elevation of the total apoptosis rate, disruption of hematopoietic cytokine balance, and downregulation of Notch pathway-related proteins. The FZBX-medicated serum notably enhanced the proliferative activity; in 5-FU-injured MSCs (P < .001), FZBX ameliorated 5-FU-induced G0/G1 phase arrest, reduced early and late apoptosis rates, and restored the hematopoietic cytokine balance (P < .001). Transcriptomic analysis revealed a significant upregulation of multiple Notch pathway components (P < .001), and PPI network analysis confirmed their functional interplay. Western blot further indicated that FZBX activated the Notch signaling pathway by upregulating the expression of Jagged1, Notch1, and Notch2.

The findings suggest that FZBX may protect against CIM by modulating MSCs function, at least partially via the Notch signaling pathway, and offers a promising therapeutic strategy.