Abstract Background The hyper-inflammatory response mediated by M1-polarized macrophages is a pivotal driver of pathology in Staphylococcus aureus (SA) pneumonia. The immunometabolic mechanisms triggering this detrimental polarization remain a critical knowledge gap. This study aims to investigate the role of glycolytic metabolic reprogramming in this process. Methods Transcriptomic and bioinformatic analyses were performed on SA-infected macrophages. Key findings were subsequently validated using a publicly available murine dataset of SA pneumonia (GSE38053). SA-induced glycolytic reprogramming was demonstrated both in vitro and in vivo. The functional roles of the identified glycolytic regulators HIF-1α and PFKFB3 were explicitly tested via shRNA-mediated knockdown in macrophages.The therapeutic potential of targeting this axis was evaluated in a murine model of SA pneumonia using a specific PFKFB3 inhibitor. Key assessments included glycolytic flux, expression of M1/M2 markers, cytokine production, and lung histopathology. Results SA infection triggered a profound glycolytic shift in macrophages, coupled with M1 polarization. We identified HIF-1α and its downstream target, the glycolytic activator PFKFB3, as central hubs in this response. Crucially, shRNA knockdown of either HIF-1α or PFKFB3 in macrophages significantly suppressed SA-induced glycolysis and abrogated the expression of M1 markers (CD86, iNOS, TNF-α, IL-6). In the murine SA pneumonia model, pharmacological inhibition of PFKFB3 mirrored the cellular findings, effectively reversing M1 polarization, reducing pro-inflammatory cytokine storm, and attenuating lung injury. Conclusion Our study establishes a definitive causal link wherein HIF-1α/PFKFB3-driven glycolysis is a non-redundant mechanism propelling M1 macrophage polarization in SA pneumonia. Targeting the PFKFB3 node offers a novel and potent immunometabolic strategy to reprogram macrophage function and alleviate detrimental inflammation in bacterial pneumonia. This abstract is funded by: Nanning Respiratory Disease Prevention and Control System Project
Lin et al. (Fri,) studied this question.