Autophagy selectively degrades aggregation-prone misfolded proteins caused by defective cellular proteostasis. However, the complexity of autophagy may prevent the full appreciation of how its modulation could be used as a therapeutic strategy in disease management. Here, we define a molecular pathway through which recombinant IL-1 receptor antagonist (IL-1Ra, anakinra) affects cellular proteostasis independently from the IL-1 receptor (IL-1R1). Anakinra promoted H2O2-driven autophagy through a xenobiotic sensing pathway involving the aryl hydrocarbon receptor that, activated through the indoleamine 2,3-dioxygenase 1-kynurenine pathway, transcriptionally activated NADPH oxidase 4 independent of the IL-1R1. By coupling the mitochondrial redox balance to autophagy, anakinra improved the dysregulated proteostasis network in murine and human cystic fibrosis. We anticipate that anakinra may represent a therapeutic option in addition to its IL-1R1–dependent antiinflammatory properties by acting at the intersection of mitochondrial oxidative stress and autophagy with the capacity to restore conditions in which defective proteostasis leads to human disease.
Frank L. van de Veerdonk, Giorgia Renga, Marilena Pariano, Marina M. Bellet, Giuseppe Servillo, Francesca Fallarino, Antonella De Luca, Rossana G. Iannitti, Danilo Piobbico, Marco Gargaro, Giorgia Manni, Fiorella D’Onofrio, Claudia Stincardini, Luigi Sforna, Monica Borghi, Marilena Castelli, Stefania Pieroni, Vasileios Oikonomou, Valeria R. Villella, Matteo Puccetti, Stefano Giovagnoli, Roberta Galarini, Carolina Barola, Luigi Maiuri, Maria Agnese Della Fazia, Barbara Cellini, Vincenzo Nicola Talesa, Charles A. Dinarello, Claudio Costantini, Luigina Romani