Essential Oils from Fructus A. zerumbet Protect Human Aortic Endothelial Cells from Apoptosis Induced by Ox-LDL In Vitro

Alpinia zerumbet is a miao folk medicinal plant widely used in the Guizhou Province of southwest China that contains several bioactive constituents and possesses protective effects against cardiovascular diseases. In the present study, we evaluated the protective effect of essential oils derived from Fructus Alpiniae zerumbet (EOFAZ) on oxidized lowdensity-lipoprotein- (ox-LDL-) induced apoptosis in human aortic endothelial cells (HAECs). Following exposure to ox-LDL, HAECs presented with classical characteristics of apoptosis. However, EOFAZ ameliorated these morphological alterations and also inhibited the decrease in cell viability. In addition, EOFAZ abrogated the number of TUNEL or Hoechst 33258 stained positive cells observed after ox-LDL challenge. Investigation into the mechanisms of this inhibition revealed that EOFAZ treatment resulted in a downregulation of Bax and Caspase-3 at both the protein and mRNA expression levels. Moreover, EOFAZ was found to upregulate Bcl-2 protein and mRNA levels and to attenuate ox-LDL-induced HAECs injury caused by apoptosis, revealing both its therapeutic potential for endothelial cell injury protection and its clinical application for atherosclerosis.