Astilbin improves the therapeutic effects of mesenchymal stem cells in AKI-CKD mice by regulating macrophage polarization through PTGS2-mediated pathway

• Astilbin pretreatment enhances the therapeutic efficacy of mesenchymal stem cells in AKI-CKD mice by promoting M2 macrophage polarization via the PTGS2-mediated pathway. • AST binds to KLF4, upregulating PTGS2 expression and increasing PGE2 secretion, which drives macrophage polarization toward the M2 phenotype. • Knockdown of PTGS2 reverses the beneficial effects of AST-pretreated MSCs, confirming the pathway's critical role. • This study provides a novel strategy to improve MSC-based therapies for AKI-CKD and highlights the potential of the natural compound Astilbin in regenerative medicine.