Participation of NADPH oxidase 5 in hypoxia-induced generation of reactive oxygen species in human endothelial cells

ALVAREZ, MS; NOLLY, M; MAZZEI,L; SALVARREDI, L; QUESADA, I; CASTRO C

MENDOZA

Congreso; XL Reunión Científica Anual de la Sociedad de Biología de Cuyo; 2022

Sociedad de Biología de Cuyo

NADPH oxidase (NOX) is the main producer of reactive oxygen species (ROS) that may contribute to the pathogenesis of endothelial dysfunction (ED). In endothelial cells, ROS can be generated from sources such as NOX and mitochondria, which in turn can serve as signaling molecules in a wide variety of processes including posttranslational modification of proteins involved in Ca2+ homeostasis. The role of NOX5. a calcium-activated NOX isoform, in triggering ROS in ED is not clear. The aim of this work was to determine the implication of NOX5 in hypoxia aside from pro-atherogenic/pro-inflammatory conditions. Human umbilical vein endothelial cells (HUVECs) were treated with Angiotensin II (AngII; 10-7 M), TNF-alpha (100 ng/mL), or cobalt chloride (CoCl2), a hypoxia mimetic agent. NOX5 expression was first analyzed by RT-PCR and western blot. Then, Superoxide generation was measured by fluorescence techniques using 5 uM dihydroethidium (DHE) for 30 min in the dark at 37 °C. An increase in NOX5 protein expression was found in HUVECs stimulated with pro-inflammatory factors, and both significantly increase the expression of monocyte chemoattractant protein 1 (MCP-1) and Interleukin 32 (IL-32) (**p