Water extract of mangosteen suppresses H2O2-induced endothelial apoptosis by inhibiting oxidative stress

ABSTRACT

Excessive production of reactive oxygen species (ROS) is a major cause of endothelial apoptosis. Mangosteenextract has been shown to possess antioxidant properties. Mangosteen is commonly extracted either with semi-polarsolvent, yielding virtually pure α-mangostin, or with water, yielding a low α-mangostin concentration but includinga wide variety of other polyphenols present in the fruit. However, the effect of a water extract of mangosteen(ME) on ROS induced cell death is not yet known. This study evaluated whether ME suppresses H2O2-inducedendothelial cell death and ROS production in human endothelial cell lines. The concentrations of ME and H2O2were determined by 3-(4,5-Dimethylthiazol-2-yl)-2,5-Diphenyltetrazolium Bromide (MTT) assay. IntracellularROS levels were determined by 2', 7' dichlorodihydrofluorescein diacetate assay, and cell death rates by MTT andTerminal deoxynucleotidyl transferase dUTP Nick-End Labeling assays. mitogen-activated protein kinase (MAPK)and apoptotic proteins were analyzed by western blot. Results showed that ME concentrations of 1, 5, and 10 µg/mlwere non-toxic. ME significantly attenuated ROS formation and cell death, both in a dose-dependent manner. MEalso reduced phosphorylation of p38 MAPK as well as cleavage of caspase 3 and poly(ADP-ribose) polymerase-1.In summary, ME demonstrates anti-apoptotic effects against H2O2-induced endothelial cell death by inhibiting ROSformation and suppressing p38 MAPK.