Eucommia ulmoides extract attenuates angiotensin II-induced cardiac microvascular endothelial cell dysfunction by inactivating p53

Abstract Angiotensin II (AngII) causes endothelial dysfunction. Eucommia ulmoides extract (EUE) is documented to manipulate AngII, but its impact on cardiac microvascular endothelial cell (CMVEC) function remains unknown. This study determines the effects of EUE on AngII-treated CMVECs. CMVECs were treated with different concentrations of AngII or EUE alone and/or the p53 protein activator, WR-1065, before AngII treatment, followed by examinations of the apoptotic, migratory, proliferative, and angiogenic capacities and nitric oxide (NO), p53, von Willebrand factor (vWF), endothelin (ET)-1, endothelial NO synthase (eNOS), manganese superoxide dismutase (MnSOD), hypoxia-inducible factor (HIF)-1α, and vascular endothelial growth factor (VEGF) levels. AngII induced CMVEC dysfunction in a concentration-dependent manner. EUE enhanced the proliferative, migratory, and angiogenic capacities and NO, MnSOD, and eNOS levels but repressed apoptosis and vWF and ET-1 levels in AngII-induced dysfunctional CMVECs. Moreover, AngII increased p53 mRNA levels, p-p53 levels in the nucleus, and p53 protein levels in the cytoplasm and diminishes HIF-1α and VEGF levels in CMVECs; however, these effects were counteracted by EUE treatment. Moreover, WR-1065 abrogated the mitigating effects of EUE on AngII-induced CMVEC dysfunction by activating p53 and decreasing HIF-1α and VEGF expression. In conclusion, EUE attenuates AngII-induced CMVEC dysfunction by upregulating HIF-1α and VEGF levels via p53 inactivation.