Formononetin ameliorates abnormal bone marrow fat accumulation after chemotherapy via activating ATGL-mediated lipolysis
Description
A 4T1 breast cancer model was established in female BALB/c mice, and doxorubicin (DOX) was administered to mimic post-chemotherapy bone marrow abnormalities. Different doses of FMN and the PPARδ agonist GW501516 were administered to observe femoral histomorphology, and H&E staining was used to evaluate bone marrow cellular changes. Bioinformatics analysis of public datasets was performed to explore the potential mechanisms of FMN. Lipid accumulation in bone marrow was visualized by oil red O staining, and triglyceride (TG) content in bone marrow cells was measured biochemically. The protein expression levels of ATGL and HSL in bone marrow cells were detected by Western blot. Flow cytometry was used to analyze the immunophenotypes of bone marrow cells and peripheral blood cells. Non-targeted lipidomics was employed to characterize the lipid metabolic profiles of mouse bone marrow. The adipogenic differentiation model of 3T3-L1 cells was used to verify the effect of FMN on lipid accumulation at the cellular level. The ATGL inhibitor Atglistatin, alone or in combination with FMN, was used to verify the role of ATGL in vivo. In 4T1 tumor-bearing mice, intraperitoneal injection of DOX disrupted femoral morphology and structure. Bioinformatics analysis revealed that FMN may promote lipid degradation and inhibit lipid synthesis through regulation of the PPAR signaling pathway. Further experimental studies showed that after chemotherapy, lipid droplets accumulated in the bone marrow, TG content increased, and bone marrow adipose precursor cells were elevated. Intragastric administration of FMN at various concentrations improved DOX-induced femoral morphological damage, with the highest dose showing the most significant effect, and also reduced lipid droplet accumulation, decreased bone marrow TG levels, and reversed the DOX-induced increase in adipose precursor cells. Non-targeted lipidomics suggested that pathways including sphingolipid metabolism, sphingolipid signaling, arachidonic acid metabolism, and linoleic acid metabolism were significantly downregulated, and inhibition of arachidonic acid- and sphingolipid-related pro-inflammatory lipid metabolism pathways may reduce chronic low-grade inflammation mediated by lipid mediators and alleviate lipotoxic damage. In vitro experiments showed that FMN attenuated lipid differentiation in 3T3-L1 cells and reduced intracellular lipid droplet deposition. Further mechanistic studies revealed that FMN upregulated ATGL protein expression and significantly reduced lipid accumulation induced by the ATGL inhibitor Atglistatin. FMN activates ATGL-mediated bone marrow lipolysis, reduces DOX-induced abnormal bone marrow fat accumulation, ameliorates lipid metabolic disorders, and reconstructs the hematopoietic microenvironment after breast cancer chemotherapy.
Files
Institutions
- Zhejiang Chinese Medical UniversityZhejiang, Hangzhou