Niklas Herrle, Pedro Felipe Malacarne, Timothy Warwick, Alfredo Cabrera-Orefice, Yiheng Chen, Maedeh Gheisari, Souradeep Chatterjee, Matthias S. Leisegang, Tamim Sarakpi, Sarah Wionski, Melina Lopez, Carine Kader, Tom Teichmann, Maria-Kyriaki Drekolia, Ina Koch, Marcus Keßler, Sabine Klein, Frank Erhard Uschner, Jonel Trebicka, Steffen Brunst, Ewgenij Proschak, Stefan Günther, Mónica Rosas‐Lemus, Nina Baumgarten, Stephan Klatt, Thimoteus Speer, Sofia‐Iris Bibli, Marta Segarra, Amparo Acker‐Palmer, Julian U. G. Wagner, Ilka Wittig, Stefanie Dimmeler, Marcel H. Schulz, J. Brent Richards, Ralf Gilsbach, Travis T. Denton, Ingrid Fleming, Luciana Hannibal, Ralf P. Brandes, Flávia Rezende
Abstract Oxidative stress is a major driver of cardiovascular disease; however, the fast changes in cellular metabolism caused by short-lived reactive oxygen species (ROS) remain ill-defined. Here, we characterized changes in the endothelial cell metabolome in response to acute oxidative challenges and identified novel redox-sensitive metabolic enzymes. H 2 O 2 selectively increased the amount of α-ketoglutaramate (αKGM), a largely uncharacterized metabolite produced by glutamine transamination and an unrecognized intermediate of endothelial glutamine catabolism. In addition, H 2 O 2 impaired the catalytic activity of nitrilase-like 2 ω-amidase (NIT2), the enzyme that converts αKGM to α-ketoglutarate (αKG), by the reversible oxidation of specific cysteine residues. Moreover, a NIT2 gene variant exhibited decreased expression in humans and was associated with increased plasma αKGM concentration. Endothelial-specific knockout of NIT2 in mice increased cellular αKGM levels and impaired angiogenesis. Further, NIT2 depletion impaired endothelial cell proliferation, sprouting, and induced senescence. In conclusion, we uncover NIT2 as a redox-sensitive enzyme of the glutamine transaminase-ω-amidase pathway that acts as a metabolic switch modulating endothelial glutamine metabolism in mice and humans.