Brazilian green propolis attenuates endothelial dysfunction and oxidative stress in a preeclampsia model in vitro.

OBJECTIVES: Brazilian green propolis is notable for its ability to modulate immune cells. In preeclampsia (PE), endothelial dysfunction is caused by the release of damage-associated molecular patterns, oxidative stress, elevated pro-inflammatory cytokines, and adhesion molecules. This study aimed to evaluate the effects of propolis on biomarkers of endothelial dysfunction and oxidative stress using human umbilical vein endothelial cells (HUVECs). METHODS: HUVECs were cultured with plasma from early-onset (EOPE; n = 16) or late-onset (LOPE; n = 16) preeclamptic women, as well as from normotensive pregnant women (NT; n = 20). Cells were stimulated with HMGB1 and Hsp70, with or without propolis. This human endothelial cell-based model was used to investigate the disease-associated mechanisms relevant to PE and to evaluate propolis effects. The expression of Flt-1, VEGFR2, endoglin, E-selectin, ICAM-1 and VCAM-1 was assessed by flow cytometry. HMGB1, Hsp70, IL-6, IL-8, sFlt-1, sEng, and VEGF were measured by ELISA, and reactive oxygen species (ROS) by fluorescence assay. KEY FINDINGS: Propolis reduced endothelial activation markers, ROS generation, IL-6 and IL-8 in both PE plasma-activated cells and DAMP-stimulated cell cultures. Propolis restored angiogenic balance by increasing VEGF levels while reducing sFlt-1 and sEng levels. CONCLUSION: Propolis attenuated endothelial dysfunction, inflammatory activation, oxidative stress, and angiogenic imbalance.