A new thiol-independent mechanism of epithelial host defense against Pseudomonas aeruginosa: iNOS/NO• sabotage of theft-ferroptosis
Haider H. Dar,
Tamil S. Anthonymuthu,
Liubov A. Ponomareva,
Austin B. Souryavong,
Galina V. Shurin,
Alexandr O. Kapralov,
Vladimir A. Tyurin,
Janet S. Lee,
Rama K. Mallampalli,
Sally E. Wenzel,
Hülya Bayir,
Valerian E. Kagan
Affiliations
Haider H. Dar
Department of Environmental and Occupational Health and Center for Free Radical and Antioxidant Health, University of Pittsburgh, Pittsburgh, PA, USA; Corresponding author.
Tamil S. Anthonymuthu
Department of Critical Care Medicine, Safar Center for Resuscitation Research, Children's Neuroscience Institute, Children's Hospital of Pittsburgh, University of Pittsburgh, Pittsburgh, PA, USA
Liubov A. Ponomareva
Institute for Regenerative Medicine, IM Sechenov Moscow State Medical University, Moscow, Russia
Austin B. Souryavong
Department of Environmental and Occupational Health and Center for Free Radical and Antioxidant Health, University of Pittsburgh, Pittsburgh, PA, USA
Galina V. Shurin
Department of Environmental and Occupational Health and Center for Free Radical and Antioxidant Health, University of Pittsburgh, Pittsburgh, PA, USA
Alexandr O. Kapralov
Department of Environmental and Occupational Health and Center for Free Radical and Antioxidant Health, University of Pittsburgh, Pittsburgh, PA, USA
Vladimir A. Tyurin
Department of Environmental and Occupational Health and Center for Free Radical and Antioxidant Health, University of Pittsburgh, Pittsburgh, PA, USA
Janet S. Lee
Department of Medicine, Division of Pulmonary, Allergy, Critical Care Medicine, Acute Lung Injury Center of Excellence, University of Pittsburgh, Pittsburgh, PA, USA
Rama K. Mallampalli
Department of Internal Medicine, The Ohio State University, Columbus, OH, USA
Sally E. Wenzel
Department of Environmental and Occupational Health and Center for Free Radical and Antioxidant Health, University of Pittsburgh, Pittsburgh, PA, USA; Asthma Institute, University of Pittsburgh, PA, USA
Hülya Bayir
Department of Environmental and Occupational Health and Center for Free Radical and Antioxidant Health, University of Pittsburgh, Pittsburgh, PA, USA; Department of Critical Care Medicine, Safar Center for Resuscitation Research, Children's Neuroscience Institute, Children's Hospital of Pittsburgh, University of Pittsburgh, Pittsburgh, PA, USA; Corresponding author. Department of Environmental and Occupational Health and Center for Free Radical and Antioxidant Health University of Pittsburgh, Pittsburgh, PA, USA.
Valerian E. Kagan
Department of Environmental and Occupational Health and Center for Free Radical and Antioxidant Health, University of Pittsburgh, Pittsburgh, PA, USA; Institute for Regenerative Medicine, IM Sechenov Moscow State Medical University, Moscow, Russia; Departments of Pharmacology and Chemical Biology, Chemistry, Radiation Oncology, University of Pittsburgh, PA, USA; Corresponding author. Department of Environmental and Occupational Health and Center for Free Radical and Antioxidant Health University of Pittsburgh, Pittsburgh, PA, USA.
Ferroptosis is a redox-driven type of regulated cell death program arising from maladaptation of three metabolic pathways: glutathione homeostasis, iron handling and lipid peroxidation. Though GSH/Gpx4 is the predominant system detoxifying phospholipid hydroperoxides (PLOOH) in mammalian cells, recently Gpx4-independent regulators of ferroptosis like ferroptosis suppressor protein 1 (FSP1) in resistant cancer lines and iNOS/NO• in M1 macrophages have been discovered. We previously reported that Pseudomonas aeruginosa (PA) utilizes its 15- lipoxygenase (pLoxA) to trigger ferroptotic death in epithelial cells by oxidizing the host arachidonoyl-phosphatidylethanolamine (ETE-PE) into pro-ferroptotic 15-hydroperoxy- arachidonyl-PE (15-HpETE-PE). Here we demonstrate that PA degrades the host GPx4 defense by activating the lysosomal chaperone-mediated autophagy (CMA). In response, the host stimulates the iNOS/NO•-driven anti-ferroptotic mechanism to stymie lipid peroxidation and protect GPx4/GSH-deficient cells. By using a co-culture model system, we showed that macrophage-produced NO• can distantly prevent PA stimulated ferroptosis in epithelial cells as an inter-cellular mechanism. We further established that suppression of ferroptosis in epithelial cells by NO• is enabled through the suppression of phospholipid peroxidation, particularly the production of pro-ferroptotic 15-HpETE-PE signals. Pharmacological targeting of iNOS (NO• generation) attenuated its anti-ferroptotic function. In conclusion, our findings define a new inter-cellular ferroptosis suppression mechanism which may represent a new strategy of the host against P. aeruginosa induced theft-ferroptosis.
