Protective Effects of Alternanthera sessilis Ethanolic Extract against TNF- α or H 2 O 2 -Induced Endothelial Activation in Human Aortic Endothelial Cells

Activation of the endothelium has been shown to contribute to the early stage of vascular diseases such as atherosclerosis and hypertension. In endothelial activation, excess reactive oxygen species (ROS) production and increased expression of cell adhesion molecules cause an increase in vascular permeability. (L.) R. Br. is an edible traditional herbal plant, which has previously been shown to possess antioxidant and anti-inflammatory effects. However, the effect of on the activation of human aortic endothelial cells (HAECs) remains unknown. This study aimed to investigate the effects of on endothelial permeability, vascular cell adhesion-1 (VCAM-1) expression, production of ROS and hydrogen peroxide (H O ), and superoxide dismutase (SOD) and catalase (CAT) activities. The viability of HAECs was first determined using the MTT viability assay. The effect of on endothelial permeability was examined using the FITC-dextran permeability assay. Besides, enzyme-linked immunosorbent assay (ELISA) was done to assess soluble VCAM-1 (sVCAM-1) expression. The production of ROS and H O was studied using 2',7'-dichlorodihydrofluorescein diacetate (H -DCFDA) and Amplex Red fluorescent dyes, respectively. SOD and CAT activities were also measured using commercial kits. Our results showed that 25-200 g/mL of ethanolic extract did not cause significant death in HAECs. at 200 g/mL significantly inhibited TNF- -induced hyperpermeability of HAECs. However, did not reduce increased VCAM-1 expression induced by TNF- . also significantly reduced TNF- -induced increased ROS production, but not H O production. Furthermore, 100 M of H O decreased both SOD and CAT activities in HAECs at 2 h. ethanolic extract dramatically increased both reduced SOD and CAT activities caused by H O . The liquid chromatography-mass spectrometry (LC-MS) analysis of ethanolic extract demonstrated the presence of arachidonic acid, azadirachtin, astaxanthin, flavanole base + 3O, 2Prenyl, and vicenin 2, while the gas chromatography-mass spectrometry (GC-MS) analysis showed that the extract contains 1,3,5-dihydroxy-6-methyl-2,3-dihydro-4H-pyran-4-one, 3-deoxy-d-mannoic lactone, 4-pyrrolidinobenzaldehyde, and -hexadecanoic acid. In conclusion, our findings suggest that ethanolic extract protects against endothelial hyperpermeability and oxidative stress elicited by pro-inflammatory or prooxidant stimulus. This study reveals a therapeutic potential of in preventing endothelial activation, which is a key ev