[Background and aim] SGLT2 at apical membrane takes glucose up into the cells, and the glucose flows across the cells and is transported to the interstitium via GLUT2 at basolateral membrane in the convoluted segments of proximal tubules. In this study, we evaluated the dynamics of a fluorescence glucose analogue, 2-NBDG, in the proximal tubules of live mice treated with or without a SGLT2 inhibitor, luseogliflozin. The influx (peak cytosolic fluorescence intensity and time to achieve the peak level), and efflux (time to halve the fluorescence intensity) of 2-NBDG in the proximal tubular cells were compared in hypo-, normo- and hyperglycemic state by multiphoton microscopy.
[Results] Neither hypo- nor hyper-glycemia did not significantly affect the 2-NBDG dynamics. There was no blood glucose level-dependent difference in the efflux of 2-NBDG. Treatment with luseogliflozin, which reduced blood glucose level in hyperglycemic group, did not show significant effects on these parameters.
[Conclusion] Neither blood glucose level nor SGLT2 inhibition affect glucose uptake dynamics in proximal tubules.