(1) Purpose: To develop a mathematical model combining
physiologically
based pharmacokinetic and urinary glucose excretion (PBPK-UGE) to
simultaneously predict pharmacokinetic (PK) and UGE changes of luseogliflozin
(LUS) as well as to explore the role of sodium-glucose cotransporters
(SGLT1 and SGLT2) in renal glucose reabsorption (RGR) in humans. (2)
Methods: The PBPK-UGE model was built using physicochemical and biochemical
properties, binding kinetics data, affinity to SGLTs for glucose,
and physiological parameters of renal tubules. (3) Results: The simulations
using this model clarified that SGLT1/2 contributed 15 and 85%, respectively,
to RGR in the absence of LUS. However, in the presence of LUS, the
contribution proportion of SGLT1 rose to 52–76% in healthy
individuals and 55–83% in T2DM patients, and that of SGLT2
reduced to 24–48 and 17–45%, respectively. Furthermore,
this model supported the underlying mechanism that only 23–40%
inhibition of the total RGR with 5 mg of LUS is resulted from SGLT1’s
compensatory effect and the reabsorption activity of unbound SGLT2.
(4) Conclusion: This PBPK-UGE model can predict PK and UGE in healthy
individuals and T2DM patients and can also analyze the contribution
of SGLT1/2 to RGR with and without LUS.