Human umbilical vein endothelial cell

Human umbilical vein endothelial cell and the ECM were purchased from ScienCell Research Laboratories (San Diego, CA, United States). The ECM was composed of basal medium, 1% endothelial cell growth supplement, 5% fetal bovine serum, and 1% penicillin/streptomycin solution. HUVECs were seeded in cell culture flasks (25 cm²; NEST, Shanghai, China) coated with poly-L-lysine, and cultivated in an atmosphere with 95% humidity and 5% CO₂ at 37°C. Cells were sub-cultured by trypsinization (0.25% trypsin, 0.5 mM EDTA) when they had grown to 80∼90% confluence. Three to six passages cells were used. The culture medium was replaced with serum-free medium for 6 h before treatment with various concentrations of 1,8-cineole with or without LPS (2.5 μg/ml) as indicated for 12 h, and the vehicle control contained serum-free medium only.

Human umbilical vein endothelial cell (passage 1; purchased from ScienCell Research Laboratories, Carlsbad, CA) were cultured in supplemented endothelial medium and used at passage 3–6 as we described earlier [19 (link)]. THP-1 monocytes (ATCC) were cultured in supplemented RPMI 1640 medium (Gibco, USA) and used within 2 months as we described elsewhere [20 (link)].