Administration of SGLT2 inhibitor empagliflozin against TNF‐α induced endothelial dysfunction in human venous and arterial endothelial cells.

Abstract

IntroductionType 2 diabetes is commonly associated with vascular inflammation and endothelial dysfunction. Clinical trials have shown unexpected cardiovascular benefits of SGLT2 inhibitors (SGLT2i), a new class of glucose‐lowering agents, in diabetic individuals. We recently showed a direct cardiac class effect of SGLT2i; SGLT2i inhibit sodium hydrogen exchanger 1 (NHE‐1), reduce [Na+]c and induce vasodilation in the healthy heart. Here, we studied if the SGLT2i empagliflozin (EMPA) improves endothelial function during TNF‐α induced endothelial inflammation.MethodsHuman umbilical vein endothelial cells (HUVECs) and human coronary arterial endothelial cells (HCAECs) were pre‐incubated for 2h with either 1 μM, 3 μM EMPA or vehicle and subsequently exposed to 10 ng/mL TNF‐α in the presence of 1 μM (EMPA1), 3 μM EMPA (EMPA3) or vehicle. ROS levels (intracellular H2O2) were measured with a commercial kit and permeability was studied in a trans‐well assay using FITC‐albumin. VCAM‐1 and ICAM‐1 levels were determined using FACS analysis. Expression of (p)eNOS and caveolin1 was detected with western blot.ResultsEMPA treated HUVECs showed a tendency of reduced ROS after 48 h of TNF‐α stimulation (in nM; control 13.3±7.8, TNF 21.5±10.3 (p=0.067 vs. control) and TNF+EMPA1 16.5±6.2 (p=0.604 vs. control)). After 24 h, TNF‐α stimulation significantly increased permeability and EMPA administration did not restore this in HUVECs (albumin leakage in μg/mL: control 36.8±1.8, TNF 61.3±3.8, EMPA1 63.3±2.0). VCAM‐1 and ICAM‐1 levels were increased in both TNF and TNF+EMPA treated HUVECs after 4 h (TNF 6.4‐fold and 7.9‐fold, EMPA1 6.3‐fold and 7.6‐fold, EMPA3 5.7‐fold and 6.8‐fold respectively vs. control). Caveolin‐1 expression was 3.3‐fold increased after 6h of TNF‐α stimulation. Again, the presence of EMPA did not prevent this induction of adhesion molecule expression. Expression of peNOS/GAPDH and eNOS/GAPDH was downregulated after 24 h in both TNF (50% and 44% respectively) and EMPA1+TNF (60% and 49% respectively) conditions compared to control. Interestingly, HCAECs treated with TNF+EMPA showed recovered peNOS/GAPDH expression (TNF 69% and EMPA1 111% vs. control).ConclusionEMPA administration exhibited a trend of reduced ROS levels, but it did not affect permeability in HUVECs exposed to TNF‐α. (P)eNOS and caveolin expression remained unaffected in HUVECs, however (p)eNOS expression was recovered in HCAECs treated with EMPA. These findings may suggest endothelial cell type specific effects of EMPA during inflammation.Support or Funding InformationNone.This abstract is from the Experimental Biology 2018 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.