Hexokinase 3 promoted cytokine production of monocytes by targeting metabolic reprogramming and histone lactylation in sepsis.

Sepsis is a life-threatening organ dysfunction caused by a dysregulated host immune response to infection, and there is currently a lack of early rapid identification and effective treatment methods. During the pathogenesis of sepsis, immune cells such as monocytes exhibit abnormal activation of aerobic glycolysis. However, the mechanism of glycolysis in immune cells during sepsis remains to be elucidated. Here, we investigated the role of glycolysis-related regulatory genes in the development of sepsis. Through analysis of the GEO database, we found that HK3 is significantly elevated in the peripheral blood of sepsis patients. Receiver operating characteristic (ROC) curve analysis demonstrated that HK3, as a novel metabolic checkpoint, serves as an excellent diagnostic biomarker for sepsis. Immune cell infiltration analysis revealed a significant increase in monocyte infiltration in the peripheral blood of sepsis patients. Single-cell RNA sequencing analysis demonstrated a significant increase in HK3 expression in monocytes from the sepsis group compared to the control group. Using an LPS-induced monocyte sepsis model, we found that HK3 boosts glycolytic activity and lactate accumulation. Mechanistically, this enhances inflammatory cytokine secretion through H3K18 lactylation-dependent activation of IL-6 and TNF-α genes. Notably, targeted HK3 knockdown effectively suppressed this pro-inflammatory cascade, highlighting its critical role in sepsis pathogenesis. Our findings not only establish HK3 as a key metabolic regulator in sepsis but also elucidate its molecular mechanism in driving excessive monocyte-mediated inflammation. Moreover, we identify HK3 as a promising therapeutic target for mitigating hyperinflammatory responses in sepsis.