Inhibiting renal glucose reabsorbtion through the sodium-glucose cotransporter (SGLT) offers an insulin-independent alternative to controlling blood glucose concentrations in patients with type 2 diabetes. While the majority of glucose is reabsorbed from glomerular filtrate by SGLT2, which is predominantly expressed in the kidney S1 segment of the proximal tubule, SGLT1 reabsorbs glucose in the distal S3 segment of the renal proximal tubule as well as from the small intestine. Dapagliflozin is a first generation, selective SGLT inhibitor that blocks glucose transport with about 100-fold selectivity for SGLT2 (Ki = 6 nM; EC50 = 1.1 nM) over SGLT1 (Ki = 390 nM). After single oral doses ranging from 0.1 to 1.0 mg/kg, dapagliflozin increases urinary glucose excretion in both normal and diabetic rats, improves glucose tolerance in normal rats, and reduces hyperglycemia in Zucker diabetic fatty rats. Within two weeks of treating diabetic rats with 0.1 to 1.0 mg/kg dapagliflozin, fasting and fed glucose levels have been shown to be significantly lowered as a result of increased glucose utilization accompanied by reduced glucose production.
