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SGLT2 inhibitors act from the extracellular surface of the cell membrane.

Ghezzi C, Hirayama BA, Gorraitz E, Loo DD, Liang Y, Wright EM - Physiol Rep (2014)

Bottom Line: To address this question we expressed hSGLT2 in HEK-293T cells and determined the affinity of a specific hSGLT2 inhibitor, TA-3404 (also known as JNJ-30980924), from the extra- and intracellular side of the plasma membrane.We compared the results to those obtained using the nonselective SGLT inhibitor phlorizin, and to the effect of TA-3404 on hSGLT1.We conclude that TA-3404 only inhibits SGLT2 from the extracellular side of the plasma membrane, suggesting that it is filtered from the blood through the glomerulus and acts from within the tubule lumen.

View Article: PubMed Central - PubMed

Affiliation: Department of Physiology, Geffen School of Medicine at UCLA, Los Angeles, California.

No MeSH data available.


Related in: MedlinePlus

Inhibitors effect on [14C]‐αMDG uptake mediated by hSGLT1 and hSGLT2. [14C]‐αMDG uptake was measured in HEK‐293T cells expressing hSGLT1 or hSGLT2 in control conditions (white bars), in presence of 100 μmol/L phlorizin (Pz, light gray bars) and 300 nmol/L (hSGLT1) or 2 nmol/L (hSGLT2) TA‐3404 (TA, dark gray bars). Uptake was measured at 37°C and expressed as quantity of tracer (pmol) per minute per μg protein. Bars are means ± SE, n = 4 wells.
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fig02: Inhibitors effect on [14C]‐αMDG uptake mediated by hSGLT1 and hSGLT2. [14C]‐αMDG uptake was measured in HEK‐293T cells expressing hSGLT1 or hSGLT2 in control conditions (white bars), in presence of 100 μmol/L phlorizin (Pz, light gray bars) and 300 nmol/L (hSGLT1) or 2 nmol/L (hSGLT2) TA‐3404 (TA, dark gray bars). Uptake was measured at 37°C and expressed as quantity of tracer (pmol) per minute per μg protein. Bars are means ± SE, n = 4 wells.

Mentions: Previous studies (Koga et al. 2013) have shown that, in CHOK1 cells overexpressing hSGLT1 or hSGLT2, TA‐3404 is a potent, selective inhibitor for hSGLT2. TA‐3404 inhibited Na+‐dependent 14C‐α‐methylglucoside (α‐MDG) uptake with an IC50 of 2 nmol/L against SGLT2 and 750 nmol/L against SGLT1 (~350‐fold selectivity for SGLT2 vs. SGLT1). Hereby, we decided to confirm these results investigating the effect of TA‐3404 on hSGLT1 or hSGLT2 activity in HEK‐293T cells. Uptakes of 50 μmol/L α‐MDG into the transfected cells were measured in the presence and absence of inhibitors (Fig. 2). 100 μmol/L phlorizin (light gray bars in Fig 2) reduced the sugar uptakes by hSGLT1 and hSGLT2 to the level observed in untransfected cells. In contrast, 300 nmol/L TA‐3404 (dark bars in Fig. 2) inhibited hSGLT1 uptake by only 10% and 2 nmol/L TA‐3404 inhibited hSGLT2 sugar uptake by 50%.


SGLT2 inhibitors act from the extracellular surface of the cell membrane.

Ghezzi C, Hirayama BA, Gorraitz E, Loo DD, Liang Y, Wright EM - Physiol Rep (2014)

Inhibitors effect on [14C]‐αMDG uptake mediated by hSGLT1 and hSGLT2. [14C]‐αMDG uptake was measured in HEK‐293T cells expressing hSGLT1 or hSGLT2 in control conditions (white bars), in presence of 100 μmol/L phlorizin (Pz, light gray bars) and 300 nmol/L (hSGLT1) or 2 nmol/L (hSGLT2) TA‐3404 (TA, dark gray bars). Uptake was measured at 37°C and expressed as quantity of tracer (pmol) per minute per μg protein. Bars are means ± SE, n = 4 wells.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4208661&req=5

fig02: Inhibitors effect on [14C]‐αMDG uptake mediated by hSGLT1 and hSGLT2. [14C]‐αMDG uptake was measured in HEK‐293T cells expressing hSGLT1 or hSGLT2 in control conditions (white bars), in presence of 100 μmol/L phlorizin (Pz, light gray bars) and 300 nmol/L (hSGLT1) or 2 nmol/L (hSGLT2) TA‐3404 (TA, dark gray bars). Uptake was measured at 37°C and expressed as quantity of tracer (pmol) per minute per μg protein. Bars are means ± SE, n = 4 wells.
Mentions: Previous studies (Koga et al. 2013) have shown that, in CHOK1 cells overexpressing hSGLT1 or hSGLT2, TA‐3404 is a potent, selective inhibitor for hSGLT2. TA‐3404 inhibited Na+‐dependent 14C‐α‐methylglucoside (α‐MDG) uptake with an IC50 of 2 nmol/L against SGLT2 and 750 nmol/L against SGLT1 (~350‐fold selectivity for SGLT2 vs. SGLT1). Hereby, we decided to confirm these results investigating the effect of TA‐3404 on hSGLT1 or hSGLT2 activity in HEK‐293T cells. Uptakes of 50 μmol/L α‐MDG into the transfected cells were measured in the presence and absence of inhibitors (Fig. 2). 100 μmol/L phlorizin (light gray bars in Fig 2) reduced the sugar uptakes by hSGLT1 and hSGLT2 to the level observed in untransfected cells. In contrast, 300 nmol/L TA‐3404 (dark bars in Fig. 2) inhibited hSGLT1 uptake by only 10% and 2 nmol/L TA‐3404 inhibited hSGLT2 sugar uptake by 50%.

Bottom Line: To address this question we expressed hSGLT2 in HEK-293T cells and determined the affinity of a specific hSGLT2 inhibitor, TA-3404 (also known as JNJ-30980924), from the extra- and intracellular side of the plasma membrane.We compared the results to those obtained using the nonselective SGLT inhibitor phlorizin, and to the effect of TA-3404 on hSGLT1.We conclude that TA-3404 only inhibits SGLT2 from the extracellular side of the plasma membrane, suggesting that it is filtered from the blood through the glomerulus and acts from within the tubule lumen.

View Article: PubMed Central - PubMed

Affiliation: Department of Physiology, Geffen School of Medicine at UCLA, Los Angeles, California.

No MeSH data available.


Related in: MedlinePlus