Mechanism by Which Dapagliflozin Induces Euglycemic Ketoacidosis in Rats

Sodium-glucose transport protein 2 inhibitors (SGLT2i) are the most recent class of antidiabetic agents; however concerns have been raised about their potential to induce euglycemic ketoacidosis by an unknown mechanism. Here we report that dapagliflozin increases rates of hepatic ketogenesis (35±4 vs. 136±8 μmol/[kg-min], p<0.0001) in normal Sprague-Dawley rats by increasing plasma catecholamine (epinephrine 0.5±0.1 vs. 7.3±0.5 nM, p<0.001, norepinephrine 2.5±0.5 vs. 19.8±5.2 nM, p<0.01) and corticosterone (115±15 vs. 233±28 ng/mL, p<0.01) concentrations secondary to volume depletion (weight change -1.9±0.4% vs. -7.1±0.4%), thereby increasing white adipose tissue lipolysis, hepatic acetyl-CoA content, hepatic glucose production and hepatic ketogenesis. Dapagliflozin-induced reductions in plasma insulin concentrations were shown to be necessary but not sufficient to induce these changes since the effects of dapagliflozin to increase hepatic ketogenesis were abrogated when extracellular volume depletion was prevented with saline infusion or free access to water. Furosemide treatment induced similar volume depletion and increases in plasma catecholamine and corticosterone concentrations without any associated changes in WAT lipolysis, hepatic glucose production or hepatic ketogenesis, likely due to its lack of an effect on plasma insulin levels. Furthermore the effects of dapagliflozin to promote increased rates of hepatic ketogenesis and hepatic glucose production were dissociated from changes in plasma glucagon concentrations, which increased (89.5±3.8 vs. 379.2±11.8 ng/mL, p<0.0001) through a central mechanism following ICV injection of dapagliflozin without any alterations in body weight or ketosis, and hepatic malonyl-CoA. Taken together these data identify SGLT2i-induced dehydration as a potential target to prevent SGLT2i-induced euglycemic ketoacidosis.