Angiotensin II promotes podocyte injury by activating Arf6-Erk1/2-Nox4 signaling pathway

• Published in: PloS one Vol. 15; no. 3; p. e0229747
• Main Authors: Che, Guanghua, Gao, Hang, Hu, Qibo, Xie, Hongchang, Zhang, Yunfeng
• Format: Journal Article
• Language: English
• Published: United States Public Library of Science 02.03.2020; Public Library of Science (PLoS)
• Subjects: Adenosine diphosphate; ADP-ribosylation; ADP-ribosylation factor 6; Angiotensin; Angiotensin II; Angiotensins; Apoptosis; Binding proteins; Biology and Life Sciences; Caspase-3; Diseases; EDTA; Extracellular signal-regulated kinase; GTP-binding protein; Immunoglobulins; Inhibitors; Injuries; Levels; Medicine and Health Sciences; Molecular modelling; NAD(P)H oxidase; NOX4 protein; Oxidases; Oxygen; Pediatrics; Protein binding; Proteins; Reactive oxygen species; Research and Analysis Methods; Ribosylation; Signal transduction; Signaling; Beijing China; United States > US; China
• ISSN: 1932-6203; 1932-6203
• DOI: 10.1371/journal.pone.0229747

Angiotensin II (Ang II) is a key contributor to glomerular disease by predominantly resulting in podocyte injury, whereas the underlying molecular mechanisms has not been fully understood. This study aimed to investigate if and how ADP-ribosylation factor 6 (Arf6), a small GTP-binding protein, involves Ang II-induced cellular injury in cultured human podocytes. Cellular injury was evaluated with caspase 3 activity, reactive oxygen species (ROS) level and TUNEL assay. Arf6 activity was measured using an Arf6-GTP Pull-Down Assay. Ang II significantly enhanced Arf6 expressions accompanied by increase of Arf6-GTP. The TUNEL-positive cells as well as activated caspase 3, NADPH oxidase 4 protein (Nox4) and ROS levels were dramatically increased in Ang II-treated podocytes, which was prevented by secinH3, an Arf6 activity inhibitor. Induction of ROS by Ang II was inhibited in podocytes with Nox4 knockdown. Ang II-induced elevation of Nox4 and ROS was prevented by Arf6 knockdown. Phpspho-Erk1/2Thr202/Tyr204 levels were upregulated remarkably following Ang II treatment, and Erk inhibitor LY3214996 significantly downregulated Nox4 expression. In addition, Ang II decreased CD2AP expression. Overexpression of CD2AP prevented Ang II-induced upregulation of Arf6-GTP. Our data demonstrated that Ang II promotes ROS production and podocytes injury through activation of Arf6-Erk1/2-Nox4 signaling. We also provided evidence that Ang II activates Arf6 by degradation of CD2AP.