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Empagliflozin Decreases Myocardial Cytoplasmic Na

Antonius Baartscheer, Cees A Schumacher, Rob C I Wüst, Jan W T Fiolet, Ger J M Stienen, Ruben Coronel, Coert J Zuurbier

Diabetologia. 2017 Mar;60(3):568-573.

PMID: 27752710

Abstract:

Aims/hypothesis:
Empagliflozin (EMPA), an inhibitor of the renal sodium-glucose cotransporter (SGLT) 2, reduces the risk of cardiovascular death in patients with type 2 diabetes. The underlying mechanism of this effect is unknown. Elevated cardiac cytoplasmic Na+ ([Na+]c) and Ca2+ ([Ca2+]c) concentrations and decreased mitochondrial Ca2+ concentration ([Ca2+]m) are drivers of heart failure and cardiac death. We therefore hypothesised that EMPA would directly modify [Na+]c, [Ca2+]c and [Ca2+]m in cardiomyocytes.
Methods:
[Na+]c, [Ca2+]c, [Ca 2+]m and Na+/H+ exchanger (NHE) activity were measured fluorometrically in isolated ventricular myocytes from rabbits and rats.
Results:
An increase in extracellular glucose, from 5.5 mmol/l to 11 mmol/l, resulted in increased [Na+]c and [Ca2+]c levels. EMPA treatment directly inhibited NHE flux, caused a reduction in [Na+]c and [Ca2+]c and increased [Ca2+]m. After pretreatment with the NHE inhibitor, Cariporide, these effects of EMPA were strongly reduced. EMPA also affected [Na+]c and NHE flux in the absence of extracellular glucose.
Conclusions/interpretation:
The glucose lowering kidney-targeted agent, EMPA, demonstrates direct cardiac effects by lowering myocardial [Na+]c and [Ca2+]c and enhancing [Ca2+]m, through impairment of myocardial NHE flux, independent of SGLT2 activity.

Chemicals Related in the Paper:

Catalog Number Product Name Structure CAS Number Price
AP1301756819 Pseudocantharidin C Pseudocantharidin C 1301756-81-9 Price
AP159138804 Cariporide Cariporide 159138-80-4 Price
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