Gallic acid inhibits the growth of calf pulmonary arterial endothelial cells through cell death and glutathione depletion

Abstract

Gallic acid (GA) exhibits a number of cellular effects, including apoptosis, which is associated with oxidative stress. The present study investigated the effects of GA on calf pulmonary arterial endothelial cell (CPAEC) growth and death, along with the levels of reactive oxygen species (ROS) and glutathione (GSH). GA treatment inhibited the growth of CPAECs at 24 h, and the half-maximal inhibitory concentration (IC50) value of GA was ∼30 μM. GA treatment also induced cell death, which was accompanied by a loss of mitochondrial membrane potential (ΔΨm). GA treatment in CPAECs resulted in decreased ROS levels, including O2, whereas the number of GSH-depleted cells increased. Neither a pan-caspase inhibitor (benzyloxycarbonyl-Val-Ala-Asp-fluoromethylketone) nor buthionine sulfoximine treatment affected GA-induced cell growth inhibition, cell death, ROS and GSH levels in CPAECs, whereas co-treatment with N-acetyl-cysteine (NAC) resulted in enhanced cell growth inhibition, cell death and ΔΨm loss in these cells. Although NAC treatment did not signif cantly influence ROS levels in GA-treated CPAECs, it signif enhanced GSH depletion in these cells. In conclusion, GA inhibited the growth of CPAECs via cell death, which was associated with GSH depletion rather than alterations to ROS levels.