Hyperglycemia drive neutrophil extracellular trap formation and subsequent tissue injury in sepsis via PI3K/AKT-mediated glycolysis.

BACKGROUND

Sepsis is frequently accompanied by metabolic disturbances, in which stress hyperglycemia is closely associated with adverse clinical prognoses. Neutrophil extracellular traps (NETs) are pivotal drivers of septic inflammatory injury and disease progression. Glycolysis dominates neutrophil metabolic reprogramming and critically controls NETosis activation in inflammatory states. However, how hyperglycemia modulates NET formation during sepsis and the underlying glycolytic regulatory mechanism remain poorly elucidated. This study investigated the effect of hyperglycemia on sepsis-related NET formation and further clarified the regulatory role of PI3K/AKT-dependent glycolysis in this pathological process.

METHODS

A total of 347 septic patients were retrospectively enrolled and stratified into euglycemia, mild and severe hyperglycemia groups based on admission blood glucose levels. Clinical 28-day outcomes were analyzed, and Boruta algorithm and multivariate regression models were used to adjust confounders and assess the dose-response association between hyperglycemia and septic injury. In vivo, a cecal ligation and puncture (CLP) and LPS-induced murine septic models with exogenous glucose intervention were established. Primary neutrophils from mouse bone marrow and human peripheral blood were isolated and treated with high glucose in vitro. Neutrophil phenotypes and transcriptomic profiles were analyzed via flow cytometry and RNA sequencing. NET formation was validated by immunofluorescent detection of CitH3 and MPO, while NET-related and inflammatory factors were quantified using ELISA. Glycolytic activity was evaluated by lactate measurement. The expression levels of core PI3K/AKT glycolytic axis molecules were determined by Western blot and qRT-PCR, and histopathological staining was performed to evaluate organ tissue injury.

RESULTS

Clinical analysis of 347 septic patients revealed that admission hyperglycemia was independently and dose-dependently correlated with elevated 28-day mortality. Hyperglycemia in septic patients promoted circulating NET formation independent of neutrophil counts. In vivo, superimposed hyperglycemia exacerbated NET release, inflammatory injury, hepatic and renal damage, and mortality in septic mice. Transcriptomic and functional assays verified that hyperglycemia upregulated key glycolytic molecules (GLUT1, PFKFB3, PDK1) to enhance glycolysis and lactate production in septic neutrophils. In vitro high-glucose stimulation augmented neutrophil NETosis via glycolytic activation. Mechanistically, hyperglycemia activated PI3K/AKT signaling to drive neutrophil glycolytic reprogramming and subsequent NET formation, whereas PI3K/AKT inhibition efficiently reversed these pathological alterations.

CONCLUSION

In conclusion, admission hyperglycemia independently predicts poor prognosis in sepsis. Mechanistically, hyperglycemia activates PI3K/AKT signaling to upregulate key glycolytic molecules, thereby enhancing neutrophil glycolysis and excessive NET formation, which aggravates inflammatory organ damage and increases septic mortality. This study reveals a novel glycometabolic mechanism underlying hyperglycemia-mediated septic deterioration.