Sodium-Glucose Cotransporter Inhibition Preserves Apolipoprotein M During Acute Inflammation in Mice and Humans

BACKGROUND: Sodium-glucose cotransporter inhibitors (SGLT2is) reduce inflammation and maintain vascular integrity. Apolipoprotein M (ApoM) is crucial for vascular integrity via sphingosine-1-phosphate (S1P) signaling and is inversely linked with mortality in sepsis and COVID-19. OBJECTIVES: The authors tested if SGLT2i (dapagliflozin [Dapa]) increases ApoM in mice using lipopolysaccharide (LPS) and in humans with COVID-19. METHODS: mice (n = 3-5/group) were randomized to receive either vehicle or Dapa (1.25 mg/kg daily) for 4 days before LPS (10 mg/kg IP). Outcomes included ApoM protein levels (Western and enzyme-linked immunosorbent assay) and intravital microscopy to assess endothelial leak and neutrophil behavior. Plasma samples from ACTIV-4a participants (standard of care, n = 37; standard of care + SGLT2i, n = 15) were analyzed for circulating ApoM by enzyme-linked immunosorbent assay. Statistical analyses included two-way analysis of variance for mice and t-test or Mann-Whitney test for humans. RESULTS: Dapa restored circulating ApoM levels in LPS-treated mice (0.017 vs 0.035 [a.u./μL], P = 0.0489) and increased ApoM levels in patients randomized to SGLT2i (0.5240 vs 0.6537 [μM], P = 0.0101). LRP2 knockout blocked Dapa's effect on ApoM. In vitro, Dapa stimulated Lrp2-dependent uptake of ApoM-GFP. Dapa attenuated vascular leak induced by LPS in an ApoM-dependent manner. CONCLUSIONS: SGLT2i maintains Lrp2 levels, preserving ApoM and promoting endothelial barrier integrity in acute inflammation, indicating a novel protective mechanism of SGLT2i through ApoM preservation.