Abstract

Endothelial cells under physiological conditions can alter energy balance by alteration in synthesis, metabolism and transport of adenosine triphosphate (ATP), which failed during endothelial cell dysfunction. ATP depleted endothelial cells are unable to perform their physiological functions as energy dependent protein secretion. Isolated human umbilical vein endothelial cells (HUVEC) from fresh umbilical cords were treated with 10 mM 2-deoxyglucose and 0.1 pg/ml of oligomycin for 6 h to induce ATP depletion. Nitric oxide (NO), von Willebrand factor (vWF), lactate dehydrogenase (LDH) release and trypan-blue exclusion were compared between treated and untreated cells. We observed a slight decrease in nitric oxide levels (P = 0.09) and vWF (P = 0.395) in the setting of 49.36% ATP depletion. There was no significant change in LDH release and cell viability between treated and untreated cells (P > 0.05). Since vWF exocytosis is an energy consuming process, decreased secretion of vWF in the isolated near-half percent of ATP depletion is not seemingly at odds. The application of vWF exocytosis fades as a candidate marker for ATP depletion induced injury, in cultured endothelial cells. Nitric oxide level and vWF secretion are not candidate markers of endothelial cell dysfunction in isolated partial ATP- depleted HUVECs. Measures such as arachidonic acid synthesis may be better alternatives.

Key words: Endothelial cell dysfunction, adenosine triphosphate (ATP) depletion, nitric oxide, von Willebrand factor (vWF).

Abbreviation

ATP, Adenosine triphosphate; ox-LDL, oxidized low-density lipoprotein; vWF, von Willebrand factor; HUVEC, human umbilical vein endothelial cells; EDTA, ethylenediaminetetraacetic acid; 2DG, 2-deoxyglucose; OG,oligomycin; PBS, phosphate buffered saline; LDH, lactate dehydrogenase; KATP,adenosine triphosphate dependent potassium channels; RBECs, rat brain capillary endothelial cells.