[Total flavonoids from Sarcandra glabra promote apoptosis in leukemia K562 cells via sphingolipid metabolism and PI3K/Akt signaling pathway based on cellular metabolomics].

This study investigated the mechanism by which total flavonoids from Sarcandra glabra promote apoptosis in leukemia K562 cells using cellular metabolomics. The following groups were set up in this study: a blank control group, a dimethyl sulfoxide(DMSO) control group, and low-, medium-, and high-dose S. glabra total flavonoid groups(25, 50, and 100 mg·L~(-1)). After 48 hours of treatment, the effects of total flavonoids from S. glabra on the proliferation and apoptosis of K562 cells were assessed using chemiluminescence assay kits and flow cytometry. Untargeted metabolomics was employed to analyze differential metabolites between the DMSO control group and the high-dose total flavonoids from S. glabra group, followed by metabolic pathway enrichment analysis. Key metabolic and signaling pathways were identified through integrated analysis of differential metabolites and transcriptomics-derived differentially expressed genes. Molecular docking was conducted to analyze target interactions between key metabolites and signaling pathways, and protein expression was validated by Western blot. The results showed that, compared with the DMSO control group, both medium-and high-dose total flavonoids from S. glabra significantly suppressed K562 cell viability and promoted apoptosis. A total of 158 differential metabolites were identified by untargeted metabolomics. The top five metabolic pathways most responsive to total flavonoids from S. glabra were sphingolipid metabolism, glutathione metabolism, arginine and proline metabolism, histidine metabolism, and lysine degradation. Integrated analysis indicated that sphingolipid metabolism and the phosphatidylinositol 3-kinase(PI3K)/protein kinase B(Akt) signaling pathway were the most significantly affected. Key metabolites in the sphingolipid metabolism pathway, i.e., dihydroceramide, ceramide, and sphingosine, showed binding energies with PI3K/Akt below-5.0 kcal·mol~(-1). Western blot results confirmed that total flavonoids from S. glabra significantly suppressed the levels of p-PI3K/PI3K and p-Akt/Akt in K562 cells. In conclusion, total flavonoids from S. glabra promote apoptosis in leukemia K562 cells by regulating sphingolipid metabolism and inhibiting the PI3K/Akt signaling pathway.