Albiflorin contributes to Xuebijing-mediated protection against sepsis-associated acute kidney injury by modulating the succinate-PFKFB3 immunometabolic axis.

BACKGROUND

Xuebijing injection (XBJ) is widely used in China as an adjunctive therapy for sepsis and sepsis-associated acute kidney injury (SAKI). Here, we evaluated its immunometabolic and inflammatory effects in macrophages and identified candidate bioactive monomers to define the underlying mechanisms.

METHODS

An inflammatory model was established in RAW264.7 macrophages using lipopolysaccharide, and targeted energy metabolomics identified succinate (SA) as a key responsive metabolite. XBJ-derived monomer screening prioritized Albiflorin for mechanistic investigation. Exogenous SA replenishment, pharmacological inhibition, and siRNA-mediated knockdown were used to investigate key glycolytic nodes and examine causal relationships. Key findings were validated in bone marrow-derived macrophages (BMDMs) and in a cecal ligation and puncture (CLP)-induced SAKI rat model.

RESULTS

In RAW264.7 macrophages, XBJ markedly reduced SA, and phenotype-guided screening prioritized Albiflorin as a representative monomer for mechanistic investigation. Albiflorin improved mitochondrial respiration, attenuated oxidative stress, and restored succinate dehydrogenase activity, consistent with reduced SA accumulation. Exogenous SA replenishment partially reversed Albiflorin's anti-glycolytic and anti-inflammatory effects and restored PFKFB3 expression, whereas HIF-1α inhibition or knockdown did not block SA-induced PFKFB3 upregulation. PFKFB3 inhibition or knockdown reduced inflammatory outputs and lactate production and constrained SA-driven glycolytic enhancement. These findings were further supported in BMDMs and in a CLP-induced SAKI rat model.

CONCLUSION

This study identified SA as an XBJ-responsive metabolite linked to macrophage inflammation and prioritized Albiflorin as a representative effector monomer for mechanistic investigation. Albiflorin lowered SA burden and suppressed PFKFB3-associated glycolytic and inflammatory activation in macrophages, supporting its contribution to SAKI protection.