Figure 1.

Lactate metabolism changes under physiological and septic conditions. Alterations in lactate metabolism occur in both physiological and pathological contexts, giving rise to diverse biological effects. (Left) Under physiological conditions, lactate serves as an important "fuel" that not only acts as a signaling molecule to regulate downstream pathways but also regulates gene expression and protein function through lactylation modifications. The lactate shuttle facilitates the flow of energy between cells and promotes intercellular communication, as seen in processes like the Cori Cycle and the astrocyte-neuron lactate shuttle. (Right) In septic conditions, factors such as hypoxia, drugs, and cytokines promote glycolysis and metabolic reprogramming, leading to increased lactate production, thereby exacerbating cellular damage. Furthermore, multiple organ dysfunction increases lactate production and reduces lactate clearance, further intensifying lactate acidosis. *Created with BioRender.com. Abbreviations: MCT: Monocarboxylate Transporter; GLUT: Glucose Transporter; FAT:; Fatty Acid Transporter; FFA: Free Fatty Acid; Glu: Glucose; Gln: Glutamine; CPCR: Cytokine Production and C-Reactive Protein; TLR: Toll-Like Receptor; CREM: cAMP Response Element Modulator; LDH: Lactate Dehydrogenase; OXPHOS: Oxidative Phosphorylation.